Approved by:	re (hrs, kensmith)

	ofw_syscons.c 1.9, s3_pci.c 1.10, scgfbrndr.c 1.23, scmouse.c 1.40,
	scvgarndr.c 1.20, scvidctl.c 1.37, syscons.c 1.439, syscons.h 1.85,
	tga.c 1.8, vesa.c 1.52, vga.c 1.35

Add a font width argument to vi_load_font_t, vi_save_font_t and vi_putm_t
and do some preparations for handling 12x22 fonts (currently lots of code
implies and/or hardcodes a font width of 8 pixels). This will be required
on sparc64 which uses a default font size of 12x22 in order to add font
loading and saving support as well as to use a syscons(4)-supplied mouse
pointer image.

Approved by:	re (scottl)

  scmouse.c, 1.39:  In set_mouse_pos(), try to avoid division by zero errors.

  scvidctl.c, 1.36:
	In sc_set_text_mode(), reset fontwidth if it is <= 0.
	Eliminates division by zero errors in syscons driver.

Approved by:	re (scottl)

  Prevent division by zero errors in sc_mouse_move()
  by explicitly setting sc->font_width, in the same
  places where sc->font_size is set, instead of
  relying on the default initialized value of 0 for sc->font_width.

PR:             kern/84836
Reported by:    Andrey V. Elsukov <bu7cher at yandex dot ru>
Approved by:	re (scottl)

users has reported corrupted display with old video cards.

Submitted by:	Michal Mertl <mime traveller cz>

24, and 32 bit modes.  To use that, syscons(4) must be built with
the compile time option 'options SC_PIXEL_MODE', and VESA support (a.k.a.
vesa.ko) must be either loaded, or be compiled into the kernel.

Do not return EINVAL when the mouse state is changed to what it already is,
which seems to cause problems when you have two mice attached, and
applications are not likely obtain useful information through the EINVAL
caused by showing the mouse pointer twice.

Teach vidcontrol(8) about mode names like MODE_<NUMBER>, where <NUMBER> is
the video mode number from the vidcontrol -i mode output.  Also, revert the
video mode if something fails.

Obtained from:	DragonFlyBSD
Discussed at:	current@ with patch attached [1]
PR:		kern/71142 [2]
Submitted by:	Xuefeng DENG <dsnofe at msn com> [1],
		Cyrille Lefevre <cyrille dot lefevre at laposte dot net> [2]

Also some minor style cleanups.