Backport of "sdpmessage: Parse zero clock-rate as default" into 1.22
requested to merge tpm/gstreamer:mr-5171-backport-into-1.22-sdp-parse-clockrate-zero-as-default into 1.22
Backport of !5171 (merged) "sdpmessage: Parse zero clock-rate as default".
Commits:
- f3cd913b sdpmessage: Parse zero clock-rate as default