Backport of "sdpmessage: Don't set SDP medias from caps without media/payload/clock-rate fields" into 1.20
requested to merge tpm/gstreamer:backport-mr-2689-into-1.20-sdp-media-with-incomplete-caps into 1.20
Backport of !2689 (merged) "sdpmessage: Don't set SDP medias from caps without media/payload/clock-rate fields".
Commits: