sys: Remove $FreeBSD$: two-line .h pattern

Remove /^\s*\*\n \*\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spdx: The BSD-2-Clause-FreeBSD identifier is obsolete, drop -FreeBSD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

sys/sys: further 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.

Implement the memset_s(3) function as specified by the C11 ISO/IEC
9899:2011 Appendix K 3.7.4.1.

Other needed supporting types, defines and constraint_handler
infrastructure is added as specified in the C11 spec.

Submitted by: Tom Rix <trix@juniper.net>
Sponsored by: Juniper Networks
Discussed with: ed
MFC after: 3 weeks
Differential revision: https://reviews.freebsd.org/D9903
Differential revision: https://reviews.freebsd.org/D10161

Move intmax_t and uintmax_t type declarations to sys/_stdint.h to give
it an exposure needed for use in sys/sysctl.h.

Suggested by: bde
Sponsored by: The FreeBSD Foundation
MFC after: 2 weeks

Make the wchar_t type machine dependent.

This is required for ARM EABI. Section 7.1.1 of the Procedure Call for the
ARM Architecture (AAPCS) defines wchar_t as either an unsigned int or an
unsigned short with the former preferred.

Because of this requirement we need to move the definition of __wchar_t to
a machine dependent header. It also cleans up the macros defining the limits
of wchar_t by defining __WCHAR_MIN and __WCHAR_MAX in the same machine
dependent header then using them to define WCHAR_MIN and WCHAR_MAX
respectively.

Discussed with: bde

Add a pointless and superfluous GNUism that people at a certain large data
aggregation and advertising company seem to believe is standard.

Approved by: dim (mentor)

Don't duplicate define the stdint types.

A new jail(8) with a configuration file, to replace the work currently done
by /etc/rc.d/jail.

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

o Merge <machine/ansi.h> and <machine/types.h> into a new header
called <machine/_types.h>.
o <machine/ansi.h> will continue to live so it can define MD clock
macros, which are only MD because of gratuitous differences between
architectures.
o Change all headers to make use of this. This mainly involves
changing:
#ifdef _BSD_FOO_T_
typedef _BSD_FOO_T_ foo_t;
#undef _BSD_FOO_T_
#endif
to:
#ifndef _FOO_T_DECLARED
typedef __foo_t foo_t;
#define _FOO_T_DECLARED
#endif

Concept by: bde
Reviewed by: jake, obrien

Create a new header <machine/_stdint.h> for storing MD parts of
<stdint.h>. Previously, parts were defined in <machine/ansi.h> and
<machine/limits.h>. This resulted in two problems:
(1) Defining macros in <machine/ansi.h> gets in the way of that
header only defining types.
(2) Defining C99 limits in <machine/limits.h> adds pollution to
<limits.h>.

o Implement <sys/_types.h>, a new header for storing types that are
MI, not required to be a fixed size, and used in multiple headers.
This will grow in time, as more things move here from <sys/types.h>
and <machine/ansi.h>.
o Add missing type definitions (uint16_t and uint32_t) to
<arpa/inet.h> and <netinet/in.h>.
o Reduce pollution in <sys/types.h> by using `#if _FOO_T_DECLARED'
widgets to avoid including <sys/stdint.h>.
o Add some missing type definitions to <unistd.h> and note the ones
that still need to be added.
o Make use of <sys/_types.h> primitives in <grp.h> and <sys/types.h>.

Reviewed by: bde

o Add new header <sys/stdint.h>.
o Make <stdint.h> a symbolic link to <sys/stdint.h>.
o Move most of <sys/inttypes.h> into <sys/stdint.h>, as per C99.
o Remove <sys/inttypes.h>.
o Adjust includes in sys/types.h and boot/efi/include/ia64/efibind.h
to reflect new location of integer types in <sys/stdint.h>.
o Remove previously symbolicly linked <inttypes.h>, instead create a
new file.
o Add MD headers <machine/_inttypes.h> from NetBSD.
o Include <sys/stdint.h> in <inttypes.h>, as required by C99; and
include <machine/_inttypes.h> in <inttypes.h>, to fill in the
remaining requirements for <inttypes.h>.
o Add additional integer types in <machine/ansi.h> and
<machine/limits.h> which are included via <sys/stdint.h>.

Partially obtain from: NetBSD
Tested on: alpha, i386
Discussed on: freebsd-standards@bostonradio.org
Reviewed by: bde, fenner, obrien, wollman