media: Investigate FFMPEG backend

[sagudev]

I think that would allow us to finally get static compilation.

[philn]

FWIW static GStreamer builds are doable, see https://gitlab.freedesktop.org/gstreamer/gstreamer/#static-build

[sagudev]

But not via rust: https://gitlab.freedesktop.org/gstreamer/gstreamer/-/merge_requests/7624

[ceyusa]

iirc for android, servo-media used a static build of gstreamer. anyhoo, my comment's out-of-topic :)