bts: Log unexpected RSL message

This is useful when doing first look at failed tests in jenkins.

Change-Id: I6cdc53ff038858211b09c0a8eeec19603107ffe4
diff --git a/bts/BTS_Tests.ttcn b/bts/BTS_Tests.ttcn
index c6ce115..cecdda1 100644
--- a/bts/BTS_Tests.ttcn
+++ b/bts/BTS_Tests.ttcn
@@ -779,8 +779,11 @@
 	[not ignore_other] as_meas_res();
 	[not ignore_other] as_l1_dcch_loop();
 	[not ignore_other] as_l1_tch_loop();
+	[not ignore_other] RSL.receive(RSL_Message:?) -> value rx {
+		Misc_Helpers.f_shutdown(__BFILE__, __LINE__, fail, log2str("Rx unexpected RSL port message: ", rx));
+		}
 	[not ignore_other] RSL.receive {
-		Misc_Helpers.f_shutdown(__BFILE__, __LINE__, fail, "Unexpected RSL message received");
+		Misc_Helpers.f_shutdown(__BFILE__, __LINE__, fail, "Rx unexpected RSL port message");
 		}
 	[ignore_other] RSL.receive { repeat; }
 	}