graphics/kmscube: expose GSTREAMER option as flavor

graphics/kmscube: update to s20230926

Changes:	https://gitlab.freedesktop.org/mesa/kmscube/-/compare/53ea71e...96d63eb

graphics/kmscube: update to s20230712

Changes:	https://gitlab.freedesktop.org/mesa/kmscube/-/compare/cf4ec7f...53ea71e

graphics/kmscube: shorten GL_TAGNAME

bsd.sites.mk: Update all ports using USE_GITLAB

Replace GL_COMMIT by GL_TAGNAME in all ports. The new GL_TAGNAME is
backwards-compatible (accepting any commit hash as before), but also
understands an actual tag name. Moving to tag names where appropriate is
left to individual ports' maintainers.

Approved by:		portmgr (tcberner, mentor)
Differential Revision:	https://reviews.freebsd.org/D37077

graphics/kmscube: update to s20230413

Changes:	https://gitlab.freedesktop.org/mesa/kmscube/-/compare/3bf6ee1...cf4ec7f

graphics/kmscube: update to s20220902

Changes:	https://gitlab.freedesktop.org/mesa/kmscube/-/compare/e6386d1...3bf6ee1

Remove WWW entries moved into port Makefiles

Commit b7f05445c00f has added WWW entries to port Makefiles based on
WWW: lines in pkg-descr files.

This commit removes the WWW: lines of moved-over URLs from these
pkg-descr files.

Approved by:		portmgr (tcberner)

Add WWW entries to port Makefiles

It has been common practice to have one or more URLs at the end of the
ports' pkg-descr files, one per line and prefixed with "WWW:". These
URLs should point at a project website or other relevant resources.

Access to these URLs required processing of the pkg-descr files, and
they have often become stale over time. If more than one such URL was
present in a pkg-descr file, only the first one was tarnsfered into
the port INDEX, but for many ports only the last line did contain the
port specific URL to further information.

There have been several proposals to make a project URL available as
a macro in the ports' Makefiles, over time.

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

graphics/mesa-libs: Bump reverse deps for libglvnd

Per discussion with bapt on helping pkg handle the changing of these
deps and avoiding impossible upgrade senarios.

PR:		246767
Reviewed by:	manu, bapt
Approved by:	x11
Differential Revision:	https://reviews.freebsd.org/D30824

Regenerate all distfiles using gitlab as source.

This regeneration is required as the new gitlab version changed
the address and the directory the source files can be downloaded.

This commit also applies some small fixes to make sure all ports using
gitlab are buildable.

Reviewed by:	mat
Approved by:	portmgr
Differential Revision:	https://reviews.freebsd.org/D29628

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

Remove # $FreeBSD$ from Makefiles.

graphics/kmscube: add new port

kmscube is a little demonstration program for how to drive bare metal
graphics without a compositor like X11, Wayland or similar, using
DRM/KMS (kernel mode setting), GBM (graphics buffer manager) and EGL
for rendering content using OpenGL or OpenGL ES.

https://gitlab.freedesktop.org/mesa/kmscube