Make the get_stream_by_ssrc method use its own locking
Make the get_stream_by_ssrc method use its own locking

tieto/farstream,kakaroto/farstream,pexip/farstream,kakaroto/farstream,shadeslayer/farstream,ahmedammar/skype_farsight2,shadeslayer/farstream,pexip/farstream,kakaroto/farstream,ahmedammar/skype_farsight2,pexip/farstream,tieto/farstream,ahmedammar/skype_farsight2,kakaroto/farstream,tieto/farstream,shadeslayer/farstream,tieto/farstream,tieto/farstream,pexip/farstream,shadeslayer/farstream,ahmedammar/skype_farsight2