Remove /^\s*\*\n \*\s+\$FreeBSD\$$\n/

Remove all sparc64 specific files
Remove all sparc64 ifdefs
Removee indireeect sparc64 ifdefs

Analysis seems to reveal that sc->keyboard >= 0 implies sc->kbd != NULL and
there's no such scenario where sc->kbd is set (and theoretically used to
rebuild sc->keyboard) with the keyboard unavailable.

Drop the index softc. The index is only explicitly needed in few places, in
which case we can just as easily grab it from sc->kbd. There's no need for
keeping sc->kbd and sc->keyboard in sync when it can be readily accomplished
with just the former.

First remove ifdefs of the unsupported option SC_DUMB_TERMINAL which
prevented building using both in the same kernel and broke regression
tests.  This option will be replaced by per-emulator supported options.

The dumb emulator rotted with KSE in r83366, but usually compiled since
it is ifdefed to nothing unless SC_DUMB_TERMINAL is defined.  The type
of an unused function parameter changed.

Both emulators rotted when 2 new methods were added while the emulators
were removed.  Only null methods are needed, but null function pointers
give panics instead.

The wildcard in the default for the unsupported option SC_DFLT_TERM
never really worked.  It tends to prefer the dumb emulator when multiple
emulators are configured.  Change it to prefer scteken for compatibility.

Mainly focus on files that use BSD 2-Clause license, however the tool I
was using misidentified many licenses so this was mostly a manual - error
prone - task.

The Software Package Data Exchange (SPDX) group provides a specification
to make it easier for automated tools to detect and summarize well known
opensource licenses. We are gradually adopting the specification, noting
that the tags are considered only advisory and do not, in any way,
superceed or replace the license texts.

Advertise this by changing the defaults to mostly red.  If you don't like
this, change them (almost) back using:
   vidcontrol -c charcolors,base=7,height=0
   vidcontrol -c mousecolors,base=0[,height=15]

The (graphics mode only) mouse cursor colors were hard-coded to a black
border and lightwhite interior.  Black for the border is the worst
possible default, since it is the same as the default black background
and not good for any dark background.  Reversing this gives the better
default of X Windows.  Coloring everything works better still.  Now
the coloring defaults to a lightwhite border and red interior.

Coloring for the character cursor is more complicated and mode
dependent.  The new coloring doesn't apply for hardware cursors.  For
non-block cursors, it only applies in graphics mode.  In text mode,
the cursor color was usually a hard-coded (dull)white for the background
only, unless the foreground was white when it was a hard-coded black
for the background only, unless the foreground was white and the
background was black it was reverse video.  In graphics mode, it was
always reverse video for the block cursor.  Reverse video is worse,
especially over cutmarking regions, since cutmarking still uses simple
reverse video (nothing better is possible in text mode) and double
reverse video for the cursor gives normal video.  Now, graphics mode
uses the same algorithm as the best case for text mode in all cases
for graphics mode.  The hard-coded sequence { white, black, } for the
background is now { red, white, blue, } where the first 2 colors can
be configured.  The blue color at the end is a sentinel which prevents
reverse video being used in most cases but breaks the compatibility
setting for white on black and black on white characters.  This will
be fixed later.  The compatibility setting is most needed for mono modes.

The previous commit to syscons.c changed sc_cnterm() to be more careful.
It followed null pointers in some cases.  But sc_cnterm() has been
unreachable for 15+ years since changes for multiple consoles turned
off calls to the the cnterm destructor for all console drivers.  Before
them, it was only called at boot time.  So no driver with an attached
console has ever been unloadable and not even the non-console destructors
have been tested much.

attribute field is curs_attr.  The base field holds user data translated
in a reversible way and is needed because current field holds this in
an irreversible way for efficiency.

Factor out some common code for the reversible translation.  This is
slightly simpler now, and much easier to expand.

Translate the magic flags value -1 to a single control flag internally
up front so other flags can be trusted later.  This can be used for the
relevant ioctl() too.

Remove CONS_CURSOR_FLAGS which contained all the control flags.  It was
unused and not useful.  After adding more flags, there will be tests on
a couple at a time but never on them all.  This API should have used this
to disallow unknown flags.

redundant initializations.

Hard-code base = 0, height = (approx. 1/8 of the boot-time font height)
in all cases, and remove the BIOS/MD support for setting these values.
This asks for an underline cursor sized for the boot-time font instead
of various less hard-coded but worse values.  I used that think that
the x86 BIOS always gave the same values as the above hard-coding, but
on 1 of my systems it gives the wrong value of base = 1.

The remaining BIOS fields are shift_state and bell_pitch.  These are now
consistently not explicitly reinitialized to 0.  All sc_get_bios_value()
functions except x86's are now empty, and the only useful thing that x86
returns is shift_state.  This really belongs in atkbdc, but heavier
use of the BIOS to read the more useful typematic rate has been removed
there.  fb still makes much heavier use of the BIOS.

to choose the best one.

The old 9x13 cursor was was sort of correct for CGA 640x200 text mode,
but distorted for all other modes.  This mode is still available on
all systems with VGA, but stopped being useful in ~1985.  It has very
unsquare pixels with an aspect ratio of 240:100 on 4:3 monitors.  On
16:9 monitors, the unsquareness in this mode is reduced to only 180:100
iff the monitor stretches the pixels to the full screen.

Newer modes and systems have smaller distortions, but with many more
variations.  Square pixels first became common with VGA 640x480 mode
on 4:3 monitors.  However, standard VGA text mode also has 9-bit wide
characters and only 25 lines, so it has 720x400 pixels.  This has
unsquare pixels with an aspect ratio of 135:100 on 4:3 monitors.  On
16:9 monitors, it gives almost-square pixels with an aspect ration of
101:100 iff the monitor stretches, but in modes that were square on
4:3 monitors square similar monitor stretching breaks the squareness.

Guess the physical aspect ratio using heuristics.  The old version of
X that I use is further from doing this using info from PnP monitors
that is unavailable in syscons (X doesn't understand if the monitor
is doing stretching and doesn't even understand how its its own mode
changes affect the pixel size).  Monitors with aspect ratio control
should be configured to _not_ stretch 4:3 modes to 16:9.  Otherwise,
use the machdep.vga_aspect_scale sysctl to compensate.  Only 1 of my
4 monitors/laptops requires this.  It always stretches to 16:9.

The mouse data has new aspect ratio fields for selecting the best
cursor and a new name field for display in debugging messages.

Selecting the mouse cursor is now a slow operation so it is not done
for every drawing of the cursor.  To avoid a new initialization method,
it is done whenever the text cursor is set or changed.  Also remove
dead code in settings of text cursors.

Use larger mouse cursors (sometimes the full 10x16 one) for 8x8 fonts
in cases where this works better (mostly in graphics mode).

corresponding to the gaps between characters.  This fixes distortion
of the cursor due to expanding it across the gaps.

Again for character width 9, when the cursor characters are not in the
graphics range (0xb0-0xdf), the gaps were always there (filled in the
background color for the previous char).  They still look strange, but
don't cause distortion.  When the cursor characters are in the graphics
range, the gaps are filled by repeating the previous line.  This gives
distortion with cilia.  Removing vertical lines reduces the distortion
to vertical cilia.

Move the default for the cursor characters out of the graphics range.
With character width 9, this gives gaps instead of distortion and
other problems.  With character width 8, it just fixes a smaller set
of other problems.  Some distortion and other problems can be recovered
using vidcontrol -M.  Presumably the default was to fill the gaps
intentionally, but it is much better to leave gaps.  The gaps can even
be considered as a feature for text processing -- they give sub-pointers
to character boundaries.  The other problems are: (1) with character
width 9, characters near the cursor are moved into the graphics range
and thus distorted if any of their 8th bits is set; (2) conflicts with
national characters in the graphics range.

The default range for the graphics cursor characters is now 8-11.  This
doesn't conflict with anything, since the glyphs for the characters in
this range are unreachable.

Use the 10x16 mouse cursor in text mode too (if the font size is >= 14).

When the character width is 9, removal of 1 or 2 vertical lines makes
10x16 cursor no wider than the 9x13 one usually was.  We could even
handle cursors 1 pixel wider in 2 character cells and gaps without
more clipping than given by the gaps (the worst case is 1 pixel in the
left cell, 1 removed in the middle gap, 8 in the right cell and 1
removed in the right gap.  The pixel in the right gap is removed so
it doesn't matter if it is in the font).

When the character width is 8, we now clip the 10-wide cursor by 1
pixel in the worst case.  This clipping is usually invisible since it
is of the border and and the border usually merges with the background
so is invisible.  There should be an option to use reverse video to
highlight the border and its tip instead of the interior (graphics
mode can do better using separate colors).  This needs the 9x13 cursor
again.

Ideas from: ache (especially about the bad default character range)