Remove $FreeBSD$: two-line .h pattern

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

This commit makes significant changes to pam_login_access(8) to bring it
up to par with the Linux pam_access(8).

Like the Linux pam_access(8) our pam_login_access(8) is a service module
for pam(3) that allows a administrator to limit access from specified
remote hosts or terminals. Unlike the Linux pam_access, pam_login_access
is missing some features which are added by this commit:

Access file can now be specified. The default remains /etc/access.conf.
The syntax is consistent with Linux pam_access.

By default usernames are matched. If the username fails to match a match
against a group name is attempted. The new nodefgroup module option will
only match a username and no attempt to match a group name is made.
Group names must be specified in brackets, "()" when nodefgroup is
specified. Otherwise the old backward compatible behavior is used.
This is consistent with Linux pam_access.

A new field separator module option allows the replacement of the default
colon (:) with any other character. This facilitates potential future
specification of X displays. This is also consistent with Linux pam_access.

A new list separator module option to replace the default space/comma/tab
with another character. This too is consistent with Linux pam_access.

Linux pam_access options not implemented in this commit are the debug
and audit options. These will be implemented at a later date.

Reviewed by: bjk, bcr (for manpages)
Approved by: des (blanket, implicit)
MFC after: 1 month
Differential Revision: https://reviews.freebsd.org/D23198

lib: further adoption of SPDX licensing ID tags.

Mainly focus on files that use BSD 2-Clause license, however the tool I
was using mis-identified 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.

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.

NAI DBA update.

WARNS=n fixes (and some stylistic issues).