BTS_Tests.ttcn: fix: properly detect Measurement Reports

The altstep for detecting Measurement Results, that was introduced
in I15782ec93d68a0dc54b2ed7a84cb70d780ba0ce1, was implemented in a
wrong way. Basically, the DL Measurement Reports (coming from the
MS) are being combined with the UL measurements, and then being
send as a RSL_MEAS_RES message, not RSL_INITDATA_IND.

Let's use the existing as_meas_res() in 'lazy' mode for that.

Change-Id: Iea5ee868ede8bfe1e2b1cbf5abcbf2844d3fe9a4
diff --git a/bts/BTS_Tests.ttcn b/bts/BTS_Tests.ttcn
index 9c749b4..f89025f 100644
--- a/bts/BTS_Tests.ttcn
+++ b/bts/BTS_Tests.ttcn
@@ -3735,14 +3735,6 @@
 	}
 }
 
-/* Expect (or not expect) SACCH messages (Measurement Reports) */
-private altstep as_rsl_sacch_ind(boolean exp_sacch) runs on ConnHdlr {
-	[exp_sacch] RSL.receive(tr_RSL_UNITDATA_IND(g_chan_nr, tr_RslLinkID_SACCH(?))) { repeat; }
-	[not exp_sacch] RSL.receive(tr_RSL_UNITDATA_IND(g_chan_nr, tr_RslLinkID_SACCH(?))) {
-		setverdict(fail, "Unexpected (SACCH) UNIT_DATA_IND message!");
-		mtc.stop;
-		}
-}
 /* Expect (or not expect) other kinds of messages */
 private altstep as_rsl_any_ind(boolean exp_any) runs on ConnHdlr {
 	[exp_any] RSL.receive { repeat; }
@@ -3767,7 +3759,7 @@
 	[] RSL.receive(tr_RSL_UNITDATA_IND(g_chan_nr, link_id, l3)) {
 		setverdict(pass);
 		}
-	[] as_rsl_sacch_ind(exp_sacch);
+	[exp_sacch] as_meas_res(verify_meas := false);
 	[] as_rsl_any_ind(exp_any);
 	[] T.timeout {
 		setverdict(fail, "Timeout waiting for UNIT_DATA_IND");
@@ -3792,7 +3784,7 @@
 	[] RSL.receive(tr_RSL_DATA_IND(g_chan_nr, link_id, l3)) {
 		setverdict(pass);
 		}
-	[] as_rsl_sacch_ind(exp_sacch);
+	[exp_sacch] as_meas_res(verify_meas := false);
 	[] as_rsl_any_ind(exp_any);
 	[] T.timeout {
 		setverdict(fail, "Timeout waiting for DATA_IND");