gst-libav: map P010, VUYA, Y410, P012, Y212, and Y412
P010 has been around for a long time.
VUYX introduced in:
https://git.ffmpeg.org/gitweb/ffmpeg.git/commit/cc5a5c986047d38b53c0f12a227b04487624e7cb
P012, Y212, XV30 (Y410), and XV36 (Y412) introduced in:
https://git.ffmpeg.org/gitweb/ffmpeg.git/commit/d75c4693fef51e8f0a1b88798530f4c5147ea906