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spdx: The BSD-2-Clause-FreeBSD identifier is obsolete, drop -FreeBSD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

aacraid: reduce max I/O size to avoid DMA issues

Reserve one page for the DMA subsystem, that may need it when the I/O
buffer is not page aligned.

Without this change, writes with the maximum allowed size failed, if:
- physical memory was fragmented, making it necessary to use one DMA
segment for each page
- the buffer to be written was not page aligned, causing the DMA
subsystem to need one extra segment

In the scenario above, the DMA subsystem would run out of segments,
resulting in a write with no SG segments, that would fail.

Reviewed by: imp
MFC after: 2 weeks
Sponsored by: Instituto de Pesquisas Eldorado (eldorado.org.br)
Differential Revision: https://reviews.freebsd.org/D30798

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

Remove ifdefs for FreeBSD 6, 7, 8 and 9. Assume we're past that.

Differential Revision: https://reviews.freebsd.org/D22539

Make aacraid(4) working on ASR8805 & ASR8402 in particular. This patch
has been in the PR system for 5 months and then on reviews for another 5.
Nobody came with any cases where it fails, while many people cried for
it to be commited & merged.

PR: 209468
Submitted by: Prasad B M <prasad.munirathnam@microsemi.com>
Reported by: Steven Peterson <scp@mainstream.net>
Approved by: scottl
MFC after: 1 month
Differential Revision: https://reviews.freebsd.org/D18408

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.

Update aacraid to version 3.2.5.

Full MSI-X interrupt support added.
Timeout and reset handling reworked, firmware flash update test added.
Support for drives with 4KB block size added.
Changes made to avoid exposure of phys. array components by default.

Approved by: scottl (mentor), emaste (co-mentor)

Driver 'aacraid' added. Supports Adaptec by PMC RAID controller families Series 6, 7, 8 and upcoming products. Older Adaptec RAID controller families are supported by the 'aac' driver.

Approved by: scottl (mentor)