MFC r272810: FV r272804:

Refactor the code and stop restore_object from creating two transactions.

Illumos issue:
    3693 restore_object uses at least two transactions to restore an object
Add vtfontcvt(8) cross-reference to vt(4) man page

MFC of r273332
MFC	r271787:

simple_httpd: cosmetic cleanups.

Many tab vs space cleanups.
Use setpgid() instead of setpgrp() which is more portable.
MFC	r271789:

lpr: replace setpgrp(2) with setpgid(2).

setpgid(2) is more portable than setpgrp(2).
The BSD variant of setpgrp is a wrapper for
setpgid(2) anyways.
MFC r273163:  Implement more functional CTL debug logging.

Setting bits in kern.cam.ctl.debug allows to log errors, commands and some
commands data respectively.
MFC r273259:
Make VPD 80h (Serial Number) transfer length match serial number length.
vt(4): Refuse to load a font if hw.vga.textmode is selected

Before, the font was loaded and the window size recalculated, giving an
unusable terminal, even if the actual font didn't change.

Reported by:	beeessdee@ruggedinbox.com
MFC of:		r273330
MFC r272763:
If we fail to send a signal after rotation, print the pidfile from which
the corresponding PID was obtained.

PR:           194143
MFC r273356:
Fix a race in pmap_emulate_accessed_dirty() that could trigger a EPT
misconfiguration VM-exit.
MFC r273577:

Return BUS_PROBE_DEFAULT instead of BUS_PROBE_VENDOR or 0 for in-tree
driver.  This change was verified by Microsoft.

Instant MFC approved by:	re (kib)
Merge remote-tracking branch 'freebsd/stable/10' into freebsd10