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/tests/msc_vlr/msc_vlr_tests.h b/tests/msc_vlr/msc_vlr_tests.h
index 82ff51a..ae0f83c 100644
--- a/tests/msc_vlr/msc_vlr_tests.h
+++ b/tests/msc_vlr/msc_vlr_tests.h
@@ -98,6 +98,7 @@
 void paging_expect_tmsi(uint32_t tmsi);
 
 void ms_sends_msg(const char *hex);
+void ms_sends_security_mode_complete();
 void gsup_rx(const char *rx_hex, const char *expect_tx_hex);
 void send_sms(struct vlr_subscr *receiver,
 	      struct vlr_subscr *sender,
@@ -126,7 +127,10 @@
 
 #define gsup_expect_tx(hex) do \
 { \
-	OSMO_ASSERT(!gsup_tx_expected); \
+	if (gsup_tx_expected) { \
+		log("Previous expected GSUP tx was not confirmed!"); \
+		OSMO_ASSERT(!gsup_tx_expected); \
+	} \
 	if (!hex) \
 		break; \
 	gsup_tx_expected = hex; \