msc: Make TC_lu_and_mo_call succeed with osmo-mg enabled osmo-msc

This is for patch https://gerrit.osmocom.org/#/c/4980 in osmo-msc

Change-Id: Ieec52d5e0da776d35d6a473bd726b368af9d5c66
diff --git a/msc_tests/MSC_Tests.ttcn b/msc_tests/MSC_Tests.ttcn
index 5afa93a..c5ab892 100644
--- a/msc_tests/MSC_Tests.ttcn
+++ b/msc_tests/MSC_Tests.ttcn
@@ -866,7 +866,8 @@
 	BSSAP.receive(tr_PDU_DTAP_MT(tr_ML3_MT_CC_ALERTING(tid)));
 
 	/* Answer. This causes TCH assignment in case of "late assignment" */
-	MNCC.send(ts_MNCC_SETUP_COMPL_req(mncc.u.signal.callref));
+	//MNCC.send(ts_MNCC_SETUP_COMPL_req(mncc.u.signal.callref));
+	MNCC.send(ts_MNCC_SETUP_rsp(mncc.u.signal.callref));
 
 	f_sleep(3.0);