multimedia/gstreamer1: Update to 1.24.8

Mk/Uses/gstreamer.mk:
- Sort, fix whitespace issues and typos
- Promote several common variables to improve maintainer QOL
*   There's now no need to set manually set PORTVERSION nor
    SOVERSION in several Makefiles
*   This will help to prevent not updating some components
*   A note has been added, however, to remind maintainers
    to remake distinfo for certain ports
- Improve documentation

multimedia/gstreamer1-plugins-webrtc:
- New port split from multimedia/gstreamer1-plugins-bad
- multimedia/gstreamer1-plugins-rust has been updated

Update gstreamer1 to upstream release 1.20.3

PR:		261585
Reviewed by:	riggs,jbeich,tcberner

Differential Revision:	https://reviews.freebsd.org/D36850

textproc/libxml2: bump all LIB_DEPENDS consumers

This is a separate commit to facilitate easier cherry-picking for
quarterly.

PR: 262853, 262940, 262877, 263126
Approved by: fluffy (mentor)

textproc/libxml2: bump all dependencies

This should make sure that all dependent ports will pick
up the new version commited with a13ec21cd733f67a9fc0dc00ab45268bdc236246

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

Remove # $FreeBSD$ from Makefiles.

gstreamer1-plugins-v4l2: fix for (some) webcams

The gstreamer v4l2 plugin probes the DMA capabilities of the webcam
device via ioctl VIDIOC_EXPBUF, expecting ENOTTY in case that's not
implemented (and will act accordingly). On our cuse, we get EINVAL
for that case (which, from my reading of ioctl(2) woulndn't be correct
here), which gstreamer neither expects nor handles and thus cannot
use this device as a video source. As we cannot fix the kernel on short
notice (cuse is part of the base system), the workaround is to handle
EINVAL like ENOTTY in this specific place. (Tested with an old
Logitech camera).

PR:		236673
Approved by:	maintainer-timeout (multimedia)

Update gstreamer1 to 1.16.2.

- The spc plugin was removed inflavor for the gsm plugin.
- Added in tree qt plugin.

Changelog: https://gstreamer.freedesktop.org/releases/1.16/#1.16.2

Update net-im/fractal to 4.2.2 to support GStreamer 1.16 (approved by
maintainer)

Thanks to antoine@ for the exp-run.

PR:		239386

Actually allow the patchfile committed in r497171 to take effect, to
fix the build on GCC-based architectures.

The failure was not detected during my own testing due to a stale copy
of the same patchfile in the masterport (not committed to svn).  The
masterport apparently was able to build even with the patch in the wrong
location.

MFH to be determined.

Pointyhat to:	linimon
Approved by:	portmgr (tier-2 blanket)

Fix build on GCC-based architectures, similar to other previous
gstreamer1-plugins-* commits:

  ./gstv4l2allocator.h:53: error: redefinition of typedef 'GstV4l2Object'

Tested on both amd64 and powerpc64.

Approved by:	portmgr (tier-2 blanket)

Update GStreamer1 to 1.6.2.
Update GStreamer1-vaapi to 0.7.0.

* Spell GStreamer consistently. [1]
* Fix typo in py3kplist in py3-gstreamer1 [1]
* Improve plugins COMMENTS (more improvements welcome)
* Actually include the gstreamer1-libav update this time.

PR:		204204 [1] (based on)
Submitted by:	olivierd@ [1]

Update gstreamer 1.0 ports to version 1.2.4.

When linking a library libA with a library libB using libtool, if libB.la
exists, libtool will add all libraries libB.la refers to (dependency_libs
field) to the linker command line and store them in the dependency_libs
field of libA.la.  So everything that subsequently links with libA will also
link to these extra libraries.  This causes too much overlinking.

This commit modifies Mk/Uses/libtool.mk so it empties the dependency_libs
field in .la libraries during staging.  However, because .la libraries have
very limited use when dependency_libs is empty it makes sense to completely
remove them during staging.

So with this commit USES=libtool is modified to remove .la libraries and a
new form (USES=libtool:keepla) is introduced in case they need to be kept
(dependency_libs is still emptied).

Stagify Gstreamer ports.
Fix build of gstreamer and gstreamer1 with glib 2.38.x [1].
Update gstreamer and gstreamer-plugins to new rules, USES=gmake pathfix,
new LIB_DEPENDS syntax.
Only pull in flex if base version is too old.
Be more selective for which OSVERSIONS we need gcc due to the clang bug.

Obtained from:	Gstreamer upstream [1]

Add NO_STAGE all over the place in preparation for the staging support (cat:
multimedia)

Add Gstreamer 1.0.7. This is the new stable version of the
Gstreamer multimedia framework.

Use the USE_GSTREAMER1 macro to select Gstreamer 1.0 plugins. A new chapter
for the porters handbook about gstreamer is a work in progress.

X related plugins are now stand alone. The gio plugin is now part of the
gstreamer1-plugins port and the oss plugins are now part of the
gstreamer1-plugins-good port.

Note that the pulseaudio plugin is missing because it needs a newer version
of pulseaudio. Also there are still a number of plugins from -bad which
haven't been ported to the 1.0 API yet.