mgcp: Disable output enabled on initialisation

Currently RTP output_enabled is set to 1 on initialisation, which
does not semantically match the initial value of conn_mode
(MGCP_CONN_NONE).

This patch changes this initial value to 0.

Sponsored-by: On-Waves ehf
diff --git a/openbsc/src/libmgcp/mgcp_protocol.c b/openbsc/src/libmgcp/mgcp_protocol.c
index 9996ba7..9055bdb 100644
--- a/openbsc/src/libmgcp/mgcp_protocol.c
+++ b/openbsc/src/libmgcp/mgcp_protocol.c
@@ -1258,7 +1258,7 @@
 	end->frames_per_packet  = 0; /* unknown */
 	end->packet_duration_ms = DEFAULT_RTP_AUDIO_PACKET_DURATION_MS;
 	end->rate               = DEFAULT_RTP_AUDIO_DEFAULT_RATE;
-	end->output_enabled	= 1;
+	end->output_enabled	= 0;
 }
 
 static void mgcp_rtp_end_init(struct mgcp_rtp_end *end)