libexec: Automated cleanup of cdefs and other formatting

Apply the following automated changes to try to eliminate
no-longer-needed sys/cdefs.h includes as well as now-empty
blank lines in a row.

Remove /^#if.*\n#endif.*\n#include\s+<sys/cdefs.h>.*\n/
Remove /\n+#include\s+<sys/cdefs.h>.*\n+#if.*\n#endif.*\n+/
Remove /\n+#if.*\n#endif.*\n+/
Remove /^#if.*\n#endif.*\n/
Remove /\n+#include\s+<sys/cdefs.h>\n#include\s+<sys/types.h>/
Remove /\n+#include\s+<sys/cdefs.h>\n#include\s+<sys/param.h>/
Remove /\n+#include\s+<sys/cdefs.h>\n#include\s+<sys/capsicum.h>/

Sponsored by: Netflix

libexec: Remove ancient SCCS tags.

Remove ancient SCCS tags from the tree, automated scripting, with two
minor fixup to keep things compiling. All the common forms in the tree
were removed with a perl script.

Sponsored by: Netflix

Purge more stray embedded $FreeBSD$ strings

These do not use __FBSDID but instead use bare char arrays.

Reviewed by: imp, emaste
Differential Revision: https://reviews.freebsd.org/D41957

General further adoption of SPDX licensing ID tags.

Mainly focus on files that use BSD 3-Clause license.

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.

Special thanks to Wind River for providing access to "The Duke of
Highlander" tool: an older (2014) run over FreeBSD tree was useful as a
starting point.

rbootd: use NULL instead of zero for pointers.

Remove the 3rd clause ("advertising clause") of the BSD license as
permitted by the University of Berkeley on July 22, 1999.

Reviewed by: imp
MFC after: 1 week

Drop support for historic ioctls and also undefine them, so that code
that checks their presence via ifdef, won't use them.

Bump __FreeBSD_version as safety measure.

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.

o __P removal
o register removal
o use new style prototypes and function definitions

$Id$ -> $FreeBSD$

Add usage(), rcsids.

Import Lite2's src/libexec, except for makekey (which was spammed
by a repository copy from 1.1.5 and patched back to Lite1) and
rbootd/bootdir/SYSHPBSD (which is binary). All changed files have
already left the vendor branch.

Zap register keyword usage and convert: bcopy -> memmove, bzero -> memset,
index -> strchr, and rindex -> strrchr.

Merge conflicts and make this compile -Wall clean.

Import of NetBSD's rbootd version 19970629

Revert $FreeBSD$ to $Id$

Make the long-awaited change from $Id$ to $FreeBSD$

This will make a number of things easier in the future, as well as (finally!)
avoiding the Id-smashing problem which has plagued developers for so long.

Boy, I'm glad we're not using sup anymore. This update would have been
insane otherwise.

Fix up programs which expect <net/if.h> to include <sys/time.h> to instead
do it themselves. (Some of these programs actually depended on this
beyond compiling the definition of struct ifinfo!) Also fix up some
other #include messes while we're at it.

add forgotten $Id$

Remove trailing whitespace.

BSD 4.4 Lite Libexec Sources