mgcp: Only if this node is supposed to send data send a dummy packet

In case the gateway is configured as recvonly, do not send a dummy
load as this is against the policy.
diff --git a/src/mgcp_ss7.c b/src/mgcp_ss7.c
index 799efa2..015c14c 100644
--- a/src/mgcp_ss7.c
+++ b/src/mgcp_ss7.c
@@ -436,7 +436,9 @@
 	 * this is a bad assumption of the network. We assume
 	 * to have the remote addr now.
 	 */
-	mgcp_send_dummy(mg_endp);
+	if (mg_endp->conn_mode == MGCP_CONN_SEND_ONLY ||
+	    mg_endp->conn_mode == MGCP_CONN_RECV_SEND)
+		mgcp_send_dummy(mg_endp);
 
 	/* update the remote end */
 	return MGCP_POLICY_CONT;