framework: convert bsd.gstreamer.mk to Uses/gstreamer.mk

- convert bsd.gstreamer.mk to Uses/gstreamer.mk
- convert ports tree to make use of USES=gstreamer
- remove duplicate dependency lines from the tree

Differential Revision: https://reviews.freebsd.org/D35097

Clean up some things

- Fix typos
- Remove duplicate variables
- Remove nop variables
- Clean up commented PORTREVISION
- Add missing USES

Reported by:	portscan

One more small cleanup, forgotten yesterday.
Reported by:	lwhsu

Remove # $FreeBSD$ from Makefiles.

Update to upstream release 21.01.

Details:
- Bugfix release, see
  https://github.com/FNA-XNA/FAudio/releases/tag/21.01

audio/faudio: update to 20.10

New Features:
    * XACT:
        * Add support for WAVESTOP notifications
        * Add support for engines without settings files (or empty settings
files)

Fixes:
    * Add power-of-two quantum fallback paths for *BSD and Emscripten
    * Return a unique error code for audio engines with a bad platform ID
    * Fix a deadlock in Wolfenstein: The Old Blood related to callbacks
    * Fix a crash for streaming WaveBanks when calling Destroy
    * stb_vorbis: Handle malloc(0) calls

Reset MAINTAINER

audio/faudio: Update to 20.09

FFMPEG has been replaced with GStreamer for a while.  Let the port
catch up.

Changes:	https://github.com/FNA-XNA/FAudio/releases/tag/20.09

audio/faudio: Update to 20.08

Changes:	https://github.com/FNA-XNA/FAudio/releases/tag/20.08

audio/faudio: Update to 20.07

Changes:	https://github.com/FNA-XNA/FAudio/releases/tag/20.07

audio/faudio: Update to 20.06

Changes:	https://github.com/FNA-XNA/FAudio/releases/tag/20.06

audio/faudio: Update to 20.05

Changes:	https://github.com/FNA-XNA/FAudio/releases/tag/20.05

audio/faudio: work around OSS audio crash

INFO: OpenAudioDevice failed: Fragment size must be a power of two

PR:		245533
Approved by:	tobik (maintainer)

audio/faudio: Update to 20.04

Changes:	https://github.com/FNA-XNA/FAudio/releases/tag/20.04

audio/faudio: Update to 20.03

Changes:	https://github.com/FNA-XNA/FAudio/releases/tag/20.03

audio/faudio: Update to 20.02

Changes:	https://github.com/FNA-XNA/FAudio/releases/tag/20.02

audio/faudio: Update to 20.01

Changes:	https://github.com/FNA-XNA/FAudio/releases/tag/20.01

audio/faudio: Update to 19.12

Changes:	https://github.com/FNA-XNA/FAudio/releases/tag/19.12

audio/faudio: Update to 19.11

Changes:	https://github.com/FNA-XNA/FAudio/releases/tag/19.11

audio/faudio: Update to 19.10

Changes:	https://github.com/FNA-XNA/FAudio/releases/tag/19.10

audio/faudio: Update to 19.09

Changes:	https://github.com/FNA-XNA/FAudio/releases/tag/19.09

multimedia/ffmpeg: update to 4.2

Changes:	https://git.ffmpeg.org/gitweb/ffmpeg.git/blob/n4.2:/Changelog
ABI:		https://abi-laboratory.pro/tracker/timeline/ffmpeg/

audio/faudio: Update to 19.08

Changes:	https://github.com/FNA-XNA/FAudio/releases/tag/19.08

Bump PORTREVISION for ports depending on the canonical version of GCC
as defined in Mk/bsd.default-versions.mk which has moved from GCC 8.3
to GCC 9.1 under most circumstances now after revision 507371.

This includes ports
 - with USE_GCC=yes or USE_GCC=any,
 - with USES=fortran,
 - using Mk/bsd.octave.mk which in turn features USES=fortran, and
 - with USES=compiler specifying openmp, nestedfct, c11, c++0x, c++11-lang,
   c++11-lib, c++14-lang, c++17-lang, or gcc-c++11-lib
plus, everything INDEX-11 shows with a dependency on lang/gcc9 now.

PR:		238330

audio/faudio: Update to 19.07

Changes:	https://github.com/FNA-XNA/FAudio/releases/tag/19.07

audio/faudio: Update to 19.06.07

Changes:	https://github.com/FNA-XNA/FAudio/releases/tag/19.06.07

audio/faudio: Update to 19.06

Changes:	https://github.com/FNA-XNA/FAudio/releases/tag/19.06

audio/faudio: Update to 19.05

Changes:	https://github.com/FNA-XNA/FAudio/releases/tag/19.05

audio/faudio: Update to 19.04

Changes:	https://github.com/FNA-XNA/FAudio/releases/tag/19.04

audio/faudio: Update to 19.03

Changes:	https://github.com/FNA-XNA/FAudio/compare/19.02-23-ge5c9c20...19.03

audio/faudio: Add missing USE_LDCONFIG

New port: audio/faudio

FAudio is an XAudio reimplementation that focuses solely on developing
fully accurate DirectX Audio runtime libraries for the FNA project,
including XAudio2, X3DAudio, XAPO, and XACT3.

WWW: https://fna-xna.github.io/

Requested by:	gerald (for future versions of emulators/wine)