Be compatible with boot code that starts right after the disk label in
the second sector by only clearing the amount of bytes needed for the
disklabel in the second sector. Previously we were clearing exactly 1
sector worth of bytes and as such writing over boot code that may have
been there.
Since we do support more than 8 partitions, make sure to set all fields
in d_partitions. For the first 8 partitions this is unneeded, but for
partitioons 9 and up this compensates for the fact that we don't clear
an entire sector anymore.
Obviously, one cannot use more than 8 partitions when using boot code
that starts right after the disk label.

Relevant GRNs:
107879 - Employ unused bytes after the disklabel in the second sector.
189500 - Revert the part of change 107879 that employs the unused bytes
	 after the disklabel in the 2nd sector for boot code.

Obtained from:	Juniper Networks, Inc.
MFC after:	3 days
cxgbe(4): knobs to enable/disable PAUSE frame based flow control.

MFC after:	1 week
Optimize the common case of injecting an interrupt into a vcpu after a HLT
by explicitly moving it out of the interrupt shadow. The hypervisor is done
"executing" the HLT and by definition this moves the vcpu out of the
1-instruction interrupt shadow.

Prior to this change the interrupt would be held pending because the VMCS
guest-interruptibility-state would indicate that "blocking by STI" was in
effect. This resulted in an unnecessary round trip into the guest before
the pending interrupt could be injected.

Reviewed by:	grehan
Add forgotten keymap files fr.kbd and fr.acc.kbd to the FILES list.

Obtained from:	thierry
MFC after:	3 days
- Fix argument list after 271387.
- While here fix typo.

Submitted by:	markj
Initialize variables before resource_int_value().

Submitted by:	Dmitry Luhtionov <dmitryluhtionov@gmail.com>
- Provide a sleepable lock to protect against ioctl() vs ioctl() races.
- Use the new lock to protect against simultaneous DIOCSTART and/or
  DIOCSTOP ioctls.

Reported & tested by:	jmallett
Sponsored by:		Nginx, Inc.
Fix ACL tests to correctly work with ZFS; previous version used wrong
paths.

PR:		191545
MFC after:	1 week
Sponsored by:	The FreeBSD Foundation
Merge remote-tracking branch 'freebsd/master' into hardened/current/userlandenhanced