STP_Tests_M3UA.TC_tmt_loadshare: Clarify log message in failure case

Change-Id: I28a86f0ea0f8df28d8d22732a8647a07a936c100
diff --git a/stp/STP_Tests_M3UA.ttcn b/stp/STP_Tests_M3UA.ttcn
index 1ad2279..3415e52 100644
--- a/stp/STP_Tests_M3UA.ttcn
+++ b/stp/STP_Tests_M3UA.ttcn
@@ -287,8 +287,8 @@
 	/* FIXME: check for extraneous messages? */
 	for (i := 1; i <= 2; i := i+1) {
 		if (num_rx[i] != iter_per_asp) {
-			setverdict(fail, "Received only ", num_rx[i], " out of expected ", iter_per_asp,
-				   "M3UA DATA messages");
+			setverdict(fail, "Received ", num_rx[i], " out of expected ", iter_per_asp,
+				   "M3UA DATA messages at M3UA port ", i);
 		}
 	}
 	setverdict(pass);