PCU: fix TC_ta_rach_imm_ass(): properly match Timing Advance

This test case would not fail even in case of Timing Advance mismatch.

Change-Id: Ife86e5e0e39f0112b854ed9a13e9c6f3c49531c9
Signed-off-by: Vadim Yanitskiy <axilirator@gmail.com>
diff --git a/pcu/PCU_Tests.ttcn b/pcu/PCU_Tests.ttcn
index e848ea6..a40819d 100644
--- a/pcu/PCU_Tests.ttcn
+++ b/pcu/PCU_Tests.ttcn
@@ -727,8 +727,11 @@
 		}
 
 		/* Make sure Timing Advance IE matches out expectations */
-		if (match(rr_msg, tr_IMM_TBF_ASS(dl := false, ta := ta))) {
-			setverdict(pass);
+		if (rr_msg.payload.imm_ass.timing_advance != ta) {
+			setverdict(fail, "Timing Advance mismatch: ",
+				   rr_msg.payload.imm_ass.timing_advance,
+				   " vs expected ", ta);
+			mtc.stop;
 		}
 	}
 }