Implement IuCS (large refactoring and addition)

osmo-nitb becomes osmo-msc
add DIUCS debug log constant
add iucs.[hc]
add msc vty, remove nitb vty
add libiudummy, to avoid linking Iu deps in tests
Use new msc_tx_dtap() instead of gsm0808_submit_dtap()
libmgcp: add mgcpgw client API
bridge calls via mgcpgw

Enable MSC specific CTRL commands, bsc_base_ctrl_cmds_install() still needs to
be split up.

Change-Id: I5b5b6a9678b458affa86800afb1ec726e66eed88
diff --git a/src/libmsc/gsm_04_11.c b/src/libmsc/gsm_04_11.c
index 3255a3b..bdf2ad7 100644
--- a/src/libmsc/gsm_04_11.c
+++ b/src/libmsc/gsm_04_11.c
@@ -55,7 +55,7 @@
 #include <openbsc/paging.h>
 #include <openbsc/bsc_rll.h>
 #include <openbsc/chan_alloc.h>
-#include <openbsc/bsc_api.h>
+#include <openbsc/msc_ifaces.h>
 #include <openbsc/osmo_msc.h>
 #include <openbsc/vlr.h>
 
@@ -128,7 +128,7 @@
 {
 	DEBUGP(DLSMS, "GSM4.11 TX %s\n", osmo_hexdump(msg->data, msg->len));
 	msg->l3h = msg->data;
-	return gsm0808_submit_dtap(conn, msg, UM_SAPI_SMS, 1);
+	return msc_tx_dtap(conn, msg);
 }
 
 /* Prefix msg with a 04.08/04.11 CP header */
@@ -1016,8 +1016,7 @@
 	/* if not, we have to start paging */
 	LOGP(DLSMS, LOGL_DEBUG, "Sending SMS: no connection open, start paging %s\n",
 	     vlr_subscr_name(vsub));
-	res = subscr_request_conn(vsub, RSL_CHANNEED_SDCCH, paging_cb_send_sms,
-				  sms);
+	res = subscr_request_conn(vsub, paging_cb_send_sms, sms, "send SMS");
 	if (!res) {
 		send_signal(S_SMS_UNKNOWN_ERROR, NULL, sms, GSM_PAGING_BUSY);
 		sms_free(sms);