osmux: Provide correct local port during mgcp resp

Also document some possible future improvements for local addr.

Change-Id: I12c8fcdc8b772b9f92a70774406d4662f44bd9a9
diff --git a/src/libosmo-mgcp/mgcp_protocol.c b/src/libosmo-mgcp/mgcp_protocol.c
index 609b5fb..0831abb 100644
--- a/src/libosmo-mgcp/mgcp_protocol.c
+++ b/src/libosmo-mgcp/mgcp_protocol.c
@@ -300,6 +300,9 @@
 					     const char *trans_id,
 					     bool add_conn_params)
 {
+	/* TODO: we may want to define another local_ip_osmux var to us for
+	   OSMUX connections. Perhaps adding a new internal API to get it based
+	   on conn type */
 	const char *addr = endp->cfg->local_ip;
 	struct msgb *sdp;
 	int rc;