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spdx: The BSD-2-Clause-FreeBSD identifier is obsolete, drop -FreeBSD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

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.

Pass the correct size argument to ioctl(DIOCGSECTORSIZE)

fifolog(1): invert order of calloc(3) arguments.

The second argment to calloc(3) should be the size, make it so.

While here be a little bit more cautious in fifolog_reader_open()
to protect in the unlikely event of an overflowed allocation.

MFC after: 3 weeks

Another couple of unsigned/ssize_t changes.

Update fifolog internals to match main version:

Rename ...write_bytes... to ...write_records..., that's what they do.

Move writer .h stuff into writer private .h file.

Change logic in writer to support both fifolog usage in FreeBSD and
Measured usage better, by always using an input buffer.

Various cleanups.

Fix a bunch of trivial whitespace mistakes and update the miniobj.h
file before the real work starts.

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

Create the altix project branch. The altix project will add support
for the SGI Altix 350 to FreeBSD/ia64. The hardware used for porting
is a two-module system, consisting of a base compute module and a
CPU expansion module. SGI's NUMAFlex architecture can be an excellent
platform to test CPU affinity and NUMA-aware features in FreeBSD.

- Import the HEAD csup code which is the basis for the cvsmode work.

Add the fifolog tools to FreeBSD.

Quoth the man-page:

Fifologs provide a compact round-robin circular storage for recording
text and binary information to permanent storage in a bounded and pre-
dictable fashion, time and space wise.

Not yet connected to the build, but feel free to test & review.