rtp_stream: Fix remote_osmux_cid_sent_to_mgw never set to true

Change-Id: I978c78976470a6c5a36da8611a203f96c9a1b2a5

src/libmsc/rtp_stream.c

@@ -324,6 +324,8 @@ static int rtp_stream_do_mgcp_verb(struct rtp_stream *rtps, enum mgcp_verb verb,
 		verb_info.port = rtps->remote.port;
 		rtps->remote_sent_to_mgw = true;
 	}
+	if (rtps->use_osmux && rtps->remote_osmux_cid >= 0)
+		rtps->remote_osmux_cid_sent_to_mgw = true;
 	rtp_stream_update_id(rtps);
 
 	osmo_mgcpc_ep_ci_request(rtps->ci, verb, &verb_info, rtps->fi, ok_event, fail_event, NULL);