Add Gstreamer1 plugins: gl, qt

[adridg]

Summary

The (base) plugin gl is not built, nor is the (good) plugin qt.

These ports add both plugins, but don't hook them to any metaport or
options. qt depends on gl. These ports are dependencies for an upcoming
application port for drone crontrollers.

Test Plan

They build, but I don't know how to test them short of using
the dependent application.

[adridg]

Adding multimedia umbrella and kwm and jbeich because they maintain certain specific gstreamer1 plugins.

[jbeich]

In D21309#463466, @adridg wrote:

Adding multimedia umbrella and kwm and jbeich because they maintain certain specific gstreamer1 plugins.

My ports aren't complicated by gstreamer1-plugins/Makefile.common. I rarely use GStreamer or touch gstreamer* ports, so can't provide good feedback.

multimedia/Makefile

135 ↗

(On Diff #60955)

Already in the tree, see graphics/gstreamer1-plugins-gl.

multimedia/gstreamer1-plugins-qt/Makefile

15 ↗

(On Diff #60955)

• Why not USE_GSTREAMER1= gl?
• Dependecies from bundles like good should probably be moved to gstreamer1-plugins/Makefile.common

[kwm]

Add qt plugin into the framework.
Make it includeable via the USE_GSTREAMER1 macro.

Don't build on i386 yet...