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spdx: The BSD-2-Clause-FreeBSD identifier is obsolete, drop -FreeBSD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

libc: drop "All rights reserved" from Foundation copyrights

This has already been done for most files that have the Foundation as
the only listed copyright holder. Do it now for files that list
multiple copyright holders, but have the Foundation copyright in its own
section.

Sponsored by: The FreeBSD Foundation

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.

Fix strcoll_l disagreeing with strxfrm by reworking the forward order case in
wcscoll_l().

Illumos fixed this while grabbing back our patches:
https://www.illumos.org/rb/r/402/

This does not 100% fix what postgresql folks reported as there is still a
remaining issue: https://www.illumos.org/issues/7962, it improves the situation

The initial issue was reported in postgresql mailing lists:
https://www.postgresql.org/message-id/flat/111D0E27-A8F3-4A84-A4E0-B0FB703863DF@s24.com#111D0E27-A8F3-4A84-A4E0-B0FB703863DF@s24.com

Submitted by: Yuri Pankov <yuri.pankov@nexenta.com>
Obtained from: Illumos
MFC after: 2 weeks

libc: spelling fixes.

Mostly on comments.

collate: Fix expansion substitions (broken upstream too)

Through testing, the user noted that some Cyrillic characters were not
sorting correctly, and this was confirmed.

After extensive testing and review, the localedef tool was eliminated
as the culprit. The sustitutions were encoded correctly in LC_COLLATE.

The error was mainly in wcscoll where character expansions were
mishandled. The main directive pass routines had to be written to
go back for a new collation value when the "state" variable was set.
Before pointers were being advanced, the second lookup was gettting
applied to the wrong character, etc.

The "eat expansion codes" section on collate.c also had a bug. Later
own, the "state" variable logic was changed to only set if next
code was greater than zero (rather than >= 0).

Some additional cleanups got captured from previous work:
1) The previous commit moved the binary search comment from the
correct location to a wrong location because it's wrong upstream
in Illumos. The comment has little value so I just removed it.
2) Don't check if pointers are null before freeing, this is
redundant as free() handles null pointers.
3) The two binary search trees were standardized wrt initialization
4) On the binary search trees, a negative "high" exits rather than
checking the table count again.

Submitted by: marino
Obtained from: DragonflyBSD

Update wcscoll forgotten in previous patch

Implement xlocale APIs from Darwin, mainly for use by libc++. This adds a
load of _l suffixed versions of various standard library functions that use
the global locale, making them take an explicit locale parameter. Also
adds support for per-thread locales. This work was funded by the FreeBSD
Foundation.

Please test any code you have that uses the C standard locale functions!

Reviewed by: das (gdtoa changes)
Approved by: dim (mentor)

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.

Prepare to handle state-dependent encodings. This mainly involves not
taking shortcuts when it comes to storing and passing around conversion
states.

Pass NULL instead of a pointer to a zeroed mbstate_t object.

Add a placeholder implementation of wcscoll() and wcsxfrm() which gives
locale-sensitive collation only in single-byte locales, and just does
binary comparison for the others with extended character sets.