libstand: Reset the seek pointer in ext2fs as done in UFS.

PR:		177328
Submitted by:	Eric van Gyzen
Reviewed by:	iedowse

Increase maximum network timeout from 20s to 120s.

Sponsored by:	Sandvine Incorporated

Modify lib/libstand/nfs.c to use NFSv3 instead of NFSv2.
This allows the nfs_getrootfh() function to return the
correct file handle size to pxe.c for pxeboot. It also
results in NFSv2 no longer being used by default anywhere
in FreeBSD. If built with OLD_NFSV2 defined, the old
code that predated this patch will be built and NFSv2
will be used. pxe.c is also modified to use this version
of nfs_getrootfh() so that pxeboot will use NFSv3 and
work for non-FreeBSD as well as FreeBSD NFS servers.

Sync. printf() of libstand(3) with sys/kern/subr_prf.c.

CVS r1.94	jhb:
Cast the integer read as the first argument for %b to an unsigned integer
so it's value is not sign extended when assigned to the uintmax_t variable
used internally by printf.  For example, if bit 31 is set in the cpuid
feature word, then %b would print out the initial value as a 16 character
hexadecimal value.  Now it only prints out an 8 character value.

CVS r1.109	njl:
Add support for 'h' and 'hh' modifiers for printf(9).

CVS r1.117	phk:
If we ignore an unknown % sequence, we must stop interpreting the remaining
% arguments because the varargs are now out of sync and there is a risk that
we might for instance dereference an integer in a %s argument.

SVN r209836	jkim:
Implement optional 'precision' for numbers.  Previously, it was parsed but
ignored.  Some third-party modules (e.g., ACPICA) prefer this format over
zero padding flag '0'.

Use panic() (which the environment is required to provide to libstand) to
implement assert() instead of relying on a non-required exit().  The exit()
invocation also did not match the semantics of the exit() routine that
current boot environments happen to require.

Implement the fo_readdir method.

Fix a bug in gzipfs that prevented lseek() from working and add lseek()
support to bzip2fs.  This fixes problems with loading compressed amd64
kernel modules containing debug symbols.

Initialize f_rabuf in the raw device case. A subsequent close()
later on would try to free it, leading to a crash.

- Don't call tftp_makereq() with too many arguments.
- Don't forget to close one of the comments.

Submitted by:	Pawel Worach