Remove $FreeBSD$: one-line sh pattern

Remove /^\s*#[#!]?\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spdx: The BSD-2-Clause-FreeBSD identifier is obsolete, drop -FreeBSD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

share and pc-sysinstall: 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.

Commit these apart because compile testing doesn't guarantee I didn't made
some nasty mistake. No functional change intended.

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.

Distinguish the cases when a dup symbol is in different versions
(evil, needs a error) or in the same version (harmless, deserves
a mere warning).

Noticed by: grehan@, tinderbox

MFp4:

- Check for duplicated symbols and suggest moving them to ObsoleteVersions.
- Improve and unify error handling.
- Make the regular expressions more uniform, robust, and less sensitive
to harmless variations in the input such as those to whitespace amount.

Reviewed by: deischen
Tested with: md5 (Version.map files in /usr/obj stay the same)

Put local symbol suppression rule into most recent (e.g. last) version
block.

Approved by: re (kensmith)

When generating the version map file, order versions oldest
first to make it easier for rtld to choose the oldest version
of a symbol.

Sumbitted by: kan

Teach bsd.lib.mk to auto generate a version map file based on
a set of symbol definitions (VERSION_DEF) and symbol mappings
(SYMBOL_MAPS).

Add an awk script to generate the version map.

Suggested by: ru
Helped by: ru
Reviewed by: ru