sys: 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

sys: Remove $FreeBSD$: one-line .c pattern

Remove /^[\s*]*__FBSDID\("\$FreeBSD\$"\);?\s*\n/

Alter the prototype of qsort_r(3) to match POSIX, which adopted the
glibc-based interface.

Unfortunately, the glibc maintainers, despite knowing the existence
of the FreeBSD qsort_r(3) interface in 2004 and refused to add the
same interface to glibc based on grounds of the lack of standardization
and portability concerns, has decided it was a good idea to introduce
their own qsort_r(3) interface in 2007 as a GNU extension with a
slightly different and incompatible interface.

With the adoption of their interface as POSIX standard, let's switch
to the same prototype, there is no need to remain incompatible.

C++ and C applications written for the historical FreeBSD interface
get source level compatibility when building in C++ mode, or when
building with a C compiler with C11 generics support, provided that
the caller passes a fifth parameter of qsort_r() that exactly matches
the historical FreeBSD comparator function pointer type and does not
redefine the historical qsort_r(3) prototype in their source code.

Symbol versioning is used to keep old binaries working.

MFC: never
Relnotes: yes
Reviewed by: cem, imp, hps, pauamma
Differential revision: https://reviews.freebsd.org/D17083

kernel: Fix several typos and minor errors

- duplicate words
- typos
- references to old versions of FreeBSD

Reviewed by: imp, benno

bhnd(4): Add support for exporting all (or a subtree) of NVRAM
properties backed by an NVRAM store.

This will be used to support:

- Serializing the current NVRAM state for writing back to flash.
- Exporting subsidiary device paths for serialization and upload to fullmac
chipsets.

Additionally, this includes an improvement to BCM-RAW format detection
to avoid matching on BCM-TEXT NVRAM data.

Approved by: adrian (mentor)
Differential Revision: https://reviews.freebsd.org/D8761

bhnd(4): NVRAM device path support.

Implements bhnd_nvram_store support for parsing and operating over NVRAM
device paths, and device path aliases, as well as tracking per-path NVRAM
variable writes.

Approved by: adrian (mentor)
Differential Revision: https://reviews.freebsd.org/D8760