libc: Purge unneeded cdefs.h

These sys/cdefs.h are not needed. Purge them. They are mostly left-over
from the $FreeBSD$ removal. A few in libc are still required for macros
that cdefs.h defines. Keep those.

Sponsored by: Netflix
Differential Revision: https://reviews.freebsd.org/D42385

Remove $FreeBSD$: one-line .c pattern

Remove /^[\s*]*__FBSDID\("\$FreeBSD\$"\);?\s*\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spdx: The BSD-2-Clause-FreeBSD identifier is obsolete, drop -FreeBSD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

acl_delete_entry(): remove write-only variable

Sponsored by: The FreeBSD Foundation
MFC after: 1 week

libc: 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.

libc: spelling fixes.

Mostly on comments.

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.

MFC r200992:

Use a local copy of entry_d for finding matches. Otherwise, if entry_d pointed
to an entry of 'acl', all ACL entries starting with entry_d would be deleted.

Approved by: emax (mentor)

Use a local copy of entry_d for finding matches. Otherwise, if entry_d pointed
to an entry of 'acl', all ACL entries starting with entry_d would be deleted.

Reviewed by: trasz
Approved by: emax (mentor)
MFC after: 3 days

Add NFSv4 ACL support to libc.

This adds the following functions to the acl(3) API: acl_add_flag_np,
acl_clear_flags_np, acl_create_entry_np, acl_delete_entry_np,
acl_delete_flag_np, acl_get_extended_np, acl_get_flag_np, acl_get_flagset_np,
acl_set_extended_np, acl_set_flagset_np, acl_to_text_np, acl_is_trivial_np,
acl_strip_np, acl_get_brand_np. Most of them are similar to what Darwin
does. There are no backward-incompatible changes.

Approved by: rwatson@

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

Adjust for brain outage that affected the previous commit.

Submitted by: Stefan Farfeleder <stefan@fafoe.narf.at>

Avoid undefined behavior:
foo[i] = bar[++i]; /* Which operator [] will be evaluated first? */

Fix the style of the SCM ID's.
I believe have made all of libc .c's as consistent as possible.

o style and consistency fixes:
- if (!var) -> if (var == NULL)
- return val; -> return (val);
o update copyright

o Separate acl_t into internal and external representations as
required by POSIX.1e. This maintains the current 'struct acl'
in the kernel while providing the generic external acl_t
interface required to complete the ACL editing library.
o Add the acl_get_entry() function.
o Convert the existing ACL utilities, getfacl and setfacl, to
fully make use of the ACL editing library.

Obtained from: TrustedBSD Project

Prepare for the inclusion of libposix1e into libc: retire the old
Makefile, add Makefile.inc needed for libc build; add
#include "namespace.h"/#include "un-namespace.h" pairs around the
includes of sys/acl.h and sys/capability.h, and an additional underscore
in front of the functions that will be overridden in libc_r.

Approved by: rwatson
Obtained from: TrustedBSD Project

Add the following POSIX 1003.1e functions and man pages:
o acl_calc_mask(): calculates the ACL mask entry associated with
the given ACL.
o acl_delete_entry(): remove a specified ACL entry from the given
ACL.

Approved by: rwatson