stp: cosmetic: use m3cfg variable in f_M3UA_listen()

Change-Id: Ic5550f17e8925c292df5b3b27cf5898edf10fd23
Related: SYS#5424
diff --git a/stp/STP_Tests_M3UA.ttcn b/stp/STP_Tests_M3UA.ttcn
index a0162cb..9f3bf0c 100644
--- a/stp/STP_Tests_M3UA.ttcn
+++ b/stp/STP_Tests_M3UA.ttcn
@@ -338,7 +338,7 @@
 		opt_list := {opt_add_local_addrs};
 	}
 
-	if (mp_m3ua_configs[i].use_tcp) {
+	if (m3cfg.use_tcp) {
 		res := M3UA_CodecPort_CtrlFunct.f_IPL4_listen(M3UA[i], mp_local_m3ua_ip[0], m3cfg.local_port,
 							      {tcp:={}});
 	} else {
@@ -349,7 +349,7 @@
 		setverdict(fail, "Could not bind M3UA socket, check your configuration");
 		mtc.stop;
 	}
-	if (mp_m3ua_configs[i].use_tcp) {
+	if (m3cfg.use_tcp) {
 		M3UA_CodecPort.f_set_tcp_segmentation(M3UA[i], res.connId);
 	}
 }