Backport of "videorate: keep pool if max_buffers is unlimited" into 1.22
requested to merge tpm/gstreamer:mr-5857-backport-into-1.22-videorate-fix-bufferpool-negotiation into 1.22
Backport of !5857 (merged) "videorate: keep pool if max_buffers is unlimited".
Commits:
- 57a4d521 videorate: keep pool if max_buffers is unlimited