bsc: Only append Osmux IEs in BSSAP AoIP

Previous to this commit, BSSAP Reset (Ack) messages contained Osmux
Support IE even if transport was SCCPLite, where those IEs are actually
meaningless.

Change-Id: If6cc0f65a0f273297a4523e5d6a7564d966f0aa6
diff --git a/bsc/MSC_ConnectionHandler.ttcn b/bsc/MSC_ConnectionHandler.ttcn
index 3cc8f8a..c7f6495 100644
--- a/bsc/MSC_ConnectionHandler.ttcn
+++ b/bsc/MSC_ConnectionHandler.ttcn
@@ -379,10 +379,12 @@
 private function UnitdataCallback(PDU_BSSAP bssap)
 runs on RAN_Emulation_CT return template PDU_BSSAP {
 	var template PDU_BSSAP resp := omit;
+	var boolean append_osmux_support := g_ran_ops.use_osmux and
+					    (g_ran_ops.transport == BSSAP_TRANSPORT_AoIP);
 
 	/* answer all RESET with a RESET ACK */
-	if (match(bssap, tr_BSSMAP_Reset(g_ran_ops.use_osmux))) {
-		resp := ts_BSSMAP_ResetAck(g_ran_ops.use_osmux);
+	if (match(bssap, tr_BSSMAP_Reset(append_osmux_support))) {
+		resp := ts_BSSMAP_ResetAck(append_osmux_support);
 	}
 
 	return resp;