sys: Remove $FreeBSD$: two-line .h pattern

Remove /^\s*\*\n \*\s+\$FreeBSD\$$\n/

spdx: The BSD-2-Clause-FreeBSD identifier is obsolete, drop -FreeBSD

The SPDX folks have obsoleted the BSD-2-Clause-FreeBSD identifier. Catch
up to that fact and revert to their recommended match of BSD-2-Clause.

Discussed with: pfg
MFC After: 3 days
Sponsored by: Netflix

sound: clean up empty lines in .c and .h files

sys/dev: further 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.

A new jail(8) with a configuration file, to replace the work currently done
by /etc/rc.d/jail.

Rearrange this code slightly to pass softcs around instead of device_t,
solving a possible panic when snd_ai2s is loaded at boot time. Also change
the device setup to indicate to the pcm layer that the device is MPSAFE.

Submitted by: Marco Trillo
Suggestions by: Ariff Abdullah

Change the way our softc is stored to use the devinfo facility provided by pcm
instead of the regular device softc interface. This brings the AOA driver in
line with the other pcm drivers.

Requested by: ariff

Add support for the I2S and davbus audio controllers found in Apple PowerPC
hardware.

Submitted by: Marco Trillo