osmux: Attach osmux to virtual trunk

It makes sense to handle one osmux socket per trunk. Since we only so
far operate one RTP/osmux trunk, let's stick to that only one for
simplicity.

Change-Id: I173266c4058d5db9479d773d7dec1304bc8f1f99
diff --git a/include/osmocom/mgcp/osmux.h b/include/osmocom/mgcp/osmux.h
index 62245a9..736025b 100644
--- a/include/osmocom/mgcp/osmux.h
+++ b/include/osmocom/mgcp/osmux.h
@@ -9,7 +9,7 @@
 	OSMUX_ROLE_BSC_NAT,
 };
 
-int osmux_init(int role, struct mgcp_config *cfg);
+int osmux_init(int role, struct mgcp_trunk *trunk);
 int osmux_enable_conn(struct mgcp_endpoint *endp, struct mgcp_conn_rtp *conn,
 		      const struct osmo_sockaddr *addr);
 void conn_osmux_disable(struct mgcp_conn_rtp *conn);