Temporarily remove the warning added r270781 - it prints the warning
regardless of whether the usage is correct or not and this generates a
LOT of noise, even when you have specified a mask.
Implement htprotmode handling.

This is separate to 11g protection - the default is to RTS protect
11n frames, including A-MPDU frames.

Tested:

* Intel 5100, STA mode
vt(4): Change the terminal and buffer sizes, even without a font

This fixes a bug where scroll lock would not work for tty #0 when using
vt_vga's textmode. The reason was that this window is created with a
static 256x100 buffer, larger than the real size of 80x25.

Now, in vt_change_font() and vt_compute_drawable_area(), we still
perform operations even of the window has no font loaded (this is the
case in textmode here vw->vw_font == NULL). One of these operation
resizes the buffer accordingly.

In vt_compute_drawable_area(), we take the terminal size as is (ie.
80x25) for the drawable area.

The font argument to vt_set_border() is removed (it was never used) and
the code now uses the computed drawable area instead of re-doing its own
calculation.

Reported by:	Harald Schmalzbauer <h.schmalzbauer_omnilan.de>
Tested by:	Harald Schmalzbauer <h.schmalzbauer_omnilan.de>
MFC after:	3 days
Use __DECONST to avoid compiler warnings (and thus build failures)
with gcc on sparc64, mips, and powerpc after r271173.
pause_sbt(): Take the cold path (ie. use DELAY()) if KDB is active

This fixes a panic in the i915 driver when one uses debug.kdb.enter=1
under vt(4).

PR:		193269
Reported by:	emaste@
Submitted by:	avg@
MFC after:	3 days
- Make hhook_run_socket() vnet-aware instead of adding CURVNET_SET() around
  the function calls.
- Fix a memory leak and stats in the case that hhook_run_socket() fails
  in soalloc().

PR:	193265
Fix support for IPv6 nameservers.

PR:		188931
Submitted by:	Takefu <takefu@airport.fm>
MFC after:	3 days
Fail rather than segfault if neither PAM_TTY nor PAM_RHOST is set.

PR:		83099
MFC after:	3 days
Use the correct idiom for default values, and ensure that the script
works correctly if the user overrides them.

PR:		193255
Submitted by:	hrs@
MFC after:	3 days
Merge remote-tracking branch 'freebsd/master' into hardened/current/segvguard