MFC r326276:

various: general adoption of SPDX licensing ID tags.

Mainly focus on files that use BSD 2-Clause license, however the tool I
was using misidentified many licenses so this was mostly a manual - error
prone - task.

The Software Package Data Exchange (SPDX) group provides a specification
to make it easier for automated tools to detect and summarize well known
opensource licenses. We are gradually adopting the specification, noting
that the tags are considered only advisory and do not, in any way,
superceed or replace the license texts.

No functional change intended.

Copy head@r302406 to stable/11 as part of the 11.0-RELEASE cycle.
Prune svn:mergeinfo from the new branch, as nothing has been merged
here.

Additional commits post-branch will follow.

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

Check l2cap socket initialisation and define L2CAP_SOCKET_CHECKED
This will fix build.

Fix world after byacc import:
- old yacc(1) use to magicially append stdlib.h, while new one don't
- new yacc(1) do declare yyparse by itself, fix redundant declaration of
'yyparse'

Approved by: des (mentor)

Do not mark Bluetooth HID device as a "potential keyboard" if its descriptor
has items with CONSUMER page. For now only check for items with KEYBOARD page.
This should prevent bthidd(8) from allocating vkbd(4) keyboard for Microsoft
Bluetooth Explorer mouse.

Reported by: Eric Anderson
MFC after: 3 days

Pacify new GCC4 warnings.

Submitted by: kan
MFC after: 1 week

Update bthidd(8) code and hook it up to the build.
bthidd(8) now was integrated with vkbd(4) and supports
multiple keyboards via vkbd(4)/kbdmux(4).

The code was tested with Apple Bluetooth keyboard and
SE k700i cell phone (remote control feature).

MFC after: 1 month

Fix problem with session termination. bthidd(8) maintains two L2CAP
connections to Bluetooth HID device. As soon as Bluetooth HID device
is powered off (or goes out of RF range) the stack will terminate both
connections. File descriptors for both connections will become active
on next select(2) call. Because bthidd(8) processes file descriptors
in order, it will detect descriptor for one of the closed connections
first and kill the session. However, there is still a second (active)
descriptor that used to point to the same session. bthidd(8) used to
assert() if it cant find session by file descriptor, which was wrong.

While I'm here fix a couple of typos in parser.y

Reported by: Eric Anderson anderson AT centtech DOT com
MFC after: 3 days

Fix typo %d -> %x

That should fix the problem with invalid PSM returned from bthidcontrol.
Pointy hat goes to me.

PR: misc/76107
Submitted by: Hiroyuki Aizu < aizu at navi dot org >
MFC after: 1 day

Check in updated bthidd(8). This is still work in progress.

Start committing Bluetooth HID (Human Interface Device) support.
Note: bthidd(8) is still not complete. Need to commit kernel
support (a-la Linux /dev/input) to feed HID events into kernel.
Also need to write bthidd(8) and bthidd.conf(5) man pages.