mdoc fix
mdoc: sort SEE ALSO.
Sort SEE ALSO
Escape Do to prevent mdoc(7) parser to get confused with the "Do" macro

Reported by:	sjg
sort SEE ALSO
sort SEE ALSO
Sort SEE ALSO
Output strerror from xo_warn

Reported by: bapt
Reviewed by: bapt, ngie

Differential Revision: https://reviews.freebsd.org/D1378
Support ALT_BREAK_TO_DEBUGGER in vt(4)

Submitted by:	Andre Albsmeier on -hackers
mdoc: improvements to SEE ALSO.
mdoc: improvements to SEE ALSO.
mdoc: improvements to SEE ALSO.
Correct a typo.
Make consistent use of the correct debug macros across the file.
On interrupt handler, save the actual data read from mbox.  The previous
macro wasn't needed and was being used with swapped arguments which always
give the same result (0) defeating the overflow check.

On initialization, do not use bcm_mbox_intr() to read the pending messages,
with the new semaphore based implementation this will lead to semaphore
being incremented on the channels that contain pending data and will make
the first read for that channel return stale data.

This fixes the hang that happens on boot while initializing the cpufreq on
Raspberry Pi.
Remove the '#undef DEBUG' that should not be committed.
- Make PCI_QUIRK_MSI_INTX_BUG work by using the ID of the actual PCI device
  for the lookup.
- For devices affected by PCI_QUIRK_MSI_INTX_BUG, ensure PCIM_CMD_INTxDIS
  is cleared when using MSI/MSI-X.
- Employ PCI_QUIRK_MSI_INTX_BUG for BCM5714(S)/BCM5715(S)/BCM5780(S) rather
  than clearing PCIM_CMD_INTxDIS unconditionally for all devices in bge(4).

MFC after:	3 days
Removes unused and duplicate headers.

Bring the wait limit on mailbox write to a more sane value.

Fix a off-by-one bug on wait time limit.

Remove extra blank line.
Submitted by:	rick Maclem
MFC after:	1 week
Use the proper markup for single quotes.