Copy stable/9 to releng/9.3 as part of the 9.3-RELEASE cycle.

Approved by: re (implicit)
Sponsored by: The FreeBSD Foundation

MFC: r264832 (partial)

- Sprinkle const and static as appropriate.
- Convert the remainder of snd_hda(4) to take advantage of nitems().
- Use DEVMETHOD_END.
- Use NULL instead of 0 for pointers.

MFC r242357:
Set all pins initial connection status to unknown (2) and then update it
with the real value in regular way if sensing is supported. This fixes
minor inconsistency when playback redirection appeared in undefined state
on boot if headphones were not connected.

MFC r242352:
Print card and subsystem IDs in verbose logs to help to identify system.
Hide some less iseful messages under debug.

MFC r241844:
remove duplicate semicolons where possible.

Approved by: cperciva (implicit)

MFC r240884:
Fix panic caused by wrong pointer dereference, left after pin sense rewrite
at r230551.

Also while there, make sense polling use reported for each node separately
instead of reporting accumulated total status.

MFC r239326:
Fix "speaker" volume control, broken at r230451.

MFC r239254:
Fix multichannel input signals tracing on some CODECs like ALC260.

MFC r238022:
Remove 14 not very useful characters " HDA CODEC PCM" from HDA pcm
device names to shorten them. PulseAudio reported to have problems with
names longer then 63 chars and at least in XMMS long names are inconvinient.

Approved by: re (kib)

MFC r233692:
Reenable unsolicited responses on CODEC if hdaa_sense_init() called again.
This fixes jack connection events handling after suspend/resume.

PR: kern/166382

MFC r230130, r230181, r230312, r230326, r230331, r230451, r230465, r230488,
r230507, r230511, r230513, r230532, r230537, r230551, r230554, r230571,
r230574, r230585, r230641, r230768, r230807, r231024:
Sync snd_hda(4) driver with HEAD.

This includes major code refactoring, HDMI support, new volume control,
automatic recording source selection, runtime reconfigureation, support
for more then 4 PCM devices on controller, multichannel recording,
additional playback/record streams, higher bandwidths support, more
informative device names and many other things.

Sponsored by: iXsystems, Inc.

Major snd_hda driver rewrite:
- Huge old hdac driver was split into three independent pieces: HDA
controller driver (hdac), HDA CODEC driver (hdacc) and HDA sudio function
driver (hdaa).
- Support for multichannel recording was added. Now, as specification
defines, driver checks input associations for pins with sequence numbers
14 and 15, and if found (usually) -- works as before, mixing signals
together. If it doesn't, it configures input association as multichannel.
- Signal tracer was improved to look for cases where several DACs/ADCs in
CODEC can work with the same audio signal. If such case found, driver
registers additional playback/record stream (channel) for the pcm device.
- New controller streams reservation mechanism was implemented. That
allows to have more pcm devices then streams supported by the controller
(usually 4 in each direction). Now it limits only number of simultaneously
transferred audio streams, that is rarely reachable and properly reported
if happens.
- Codec pins and GPIO signals configuration was exported via set of
writable sysctls. Another sysctl dev.hdaa.X.reconfig allows to trigger
driver reconfiguration in run-time.
- Driver now decodes pins location and connector type names. In some cases
it allows to hint user where on the system case connectors, related to the
pcm device, are located. Number of channels supported by pcm device,
reported now (if it is not 2), should also make search easier.
- Added workaround for digital mic on some Asus laptops/netbooks.

MFC after: 2 months
Sponsored by: iXsystems, Inc.