Import byacc 20120115

Approved by:	des (mentor)
Import byacc from invisible island, it brings us lots of compatibilities with
bison, keeping full compatibility with our previous yacc implementation.

Also bring the ability to create reentrant parser

This fix bin/140309 [1]

PR:		bin/140309 [1]
Submitted by:	Philippe Pepiot <ksh@philpep.org> [1]
Approved by:	des (mentor)
MFC after:	1 month
Regenerate usb.conf

MFC after:	3 days
Add missing \n when generating pkg.conf

Reported by:	beat
Approved by:	des (mentor)
MFC after:	1 day
Don't recurse into libssp when MK_SSP is set to no.
Re-add 'ic' and properly wrap it in the SUPERG macro.
Apply style(9) to return and switch/case statements.

Reviewed by:	delphij (prior version of the patch)
Add checks for memory allocation failures in appropriate places, and
avoid creating bad entries in the grp list as a result of memory allocation
failures while building new entries.

PR:		bin/83340
Reviewed by:	delphij (prior version of patch)
Fix panic on attaching to non-existent interface (introduced by r233937, pointed by hrs@)
Fix panic on tcpdump being attached to interface being removed (introduced by r233937, pointed by hrs@ and adrian@)
Protect most of bpf_setf() by BPF global lock

Add several forgotten assertions (thanks to adrian@)

Document current locking model inside bpf.c
Document EVENTHANDLER(9) usage inside BPF.

Approved by:       kib(mentor)
Tested by:         gnn
MFC in:            4 weeks
Fix old panic when BPF consumer attaches to destroying interface.
'flags' field is added to the end of bpf_if structure. Currently the only
flag is BPFIF_FLAG_DYING which is set on bpf detach and checked by bpf_attachd()
Problem can be easily triggered on SMP stable/[89] by the following command (sort of):
'while true; do ifconfig vlan222 create vlan 222 vlandev em0 up ; tcpdump -pi vlan222 & ; ifconfig vlan222 destroy ; done'

Fix possible use-after-free when BPF detaches itself from interface, freeing bpf_bif memory,
while interface is still UP and there can be routes via this interface.
Freeing is now delayed till ifnet_departure_event is received via eventhandler(9) api.

Convert bpfd rwlock back to mutex due lack of performance gain (currently checking if packet
matches filter is done without holding bpfd lock and we have to acquire write lock if packet matches)

Approved by:      kib(mentor)
MFC in:            4 weeks
Call bpf_jitter() before acquiring BPF global lock due to malloc() being used inside bpf_jitter.

Eliminate bpf_buffer_alloc() and allocate BPF buffers on descriptor creation and BIOCSBLEN ioctl.
This permits us not to allocate buffers inside bpf_attachd() which is protected by global lock.

Approved by:      kib(mentor)
MFC in:            4 weeks
Make most BPF ioctls() SMP-safe.

Approved by:      kib(mentor)
MFC in:            4 weeks
Rename ath_tx_cleanup() -> ath_tx_tid_cleanup() in order to not clash
with a symbol in if_ath.c
For now, add a quick debugging patch to log when the hw TXQ != the TID/AC.
Wait until completion context unwinds before retrying CCBs that have been
queued internally.  This works around issue in the isci HAL where it cannot
accept new I/O to a device after a resetting->ready state transition until
the completion context has unwound.

This issue was found by submitting non-tagged CCBs through pass(4) interface
to a SATA disk with an extremely small timeout value (5ms).  This would trigger
internal resets with I/O in the isci(4) internal queues.

The small timeout value had not been intentional (and original reporter has
since changed his test to use 5sec instead), but it did uncover this corner
case that would result in a hung disk.

Sponsored by: Intel
Reported and tested by: Ravi Pokala <rpokala at panasas dot com>
Reviewed by: scottl (earlier version)
MFC after: 1 week
Add missing header needed by free()

Reported by:	tinderbox
Remove redundant declaration of yyparse

Reported by:	tinderbox
Ignore the power button press event for resuming rather than starting
shutdown.

MFC after:	2 days
Correct use_screen() and use_window() prototypes in curs_threads(3x).

Submitted by:	Yanhui Shen <shen.elf@gmail.com>
MFC after:	3 days
Fix up some corner cases with aggregation handling.

I've come across a weird scenario in net80211 where two TX streams will
happily attempt to setup an aggregation session together.
If we're very lucky, it happens concurrently on separate CPUs and the
total lack of locking in the net80211 aggregation code causes this stuff
to race. Badly.

So >1 call would occur to the ath(4) addba start, but only one call would
complete to addba complete or timeout.  The TID would thus stay paused.

The real fix is to implement some proper per-node (or maybe per-TID)
locking in net80211, which then could be leveraged by the ath(4) TX
aggregation code.

Whilst I'm at it, shuffle around the debugging messages a bit.
I like to keep people on their toes.