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

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

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.

Improve portability #defines for compiling aicasm on other systems.

Submitted by: Robert Millan rmh debian.org
Obtained from: Debian GNU/kFreeBSD

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

Code cleanups to make this WARNS=6 clean.

PR: bin/96128

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

Fix a group of typos:
preceed -> precede,
preceeded -> preceded,
preceeding -> preceding.

Submitted by: Andre Guibert de Bruet <andy@siliconlandmark.com>

Start each of the license/copyright comments with /*-, minor shuffle of lines

Update assembler syntax and assembler to allow generation of register
description tables used for diagnostic "pretty printing".

Add macro functionality.

Staticize and allow unique naming of data structures so that more
than on sequencer program can be statically compiled into the kernel
at a time.