bsc: TC_ho_int: verify TSC in Chan Act

OS#5244 reports an error in the Training Sequence Code used in the
Channel Activation for a handover target channel. Verify the TSC to
uncover this bug.

Related: SYS#4895, OS#5244
Related: Iae20df4387c3d75752301bd5daeeea7508966393 (osmo-bsc)
Change-Id: I1ed6f068c85b01e5a2d7b5f2651498a1521f89af
diff --git a/bsc/BSC_Tests.ttcn b/bsc/BSC_Tests.ttcn
index 9e4ddff..e8bb99c 100644
--- a/bsc/BSC_Tests.ttcn
+++ b/bsc/BSC_Tests.ttcn
@@ -5081,7 +5081,7 @@
 		handover_done := false,
 		old_chan_nr := -
 	};
-	/* issue hand-over command on VTY */
+	/* issue hand-over command on VTY, from BTS 0 to BTS 1 */
 	f_vty_handover(BSCVTY, 0, 0, g_chan_nr, 1);
 	/* temporarily suspend DChan processing on BTS1 to avoid race with RSLEM_register */
 	f_rslem_suspend(RSL1_PROC);
@@ -5103,9 +5103,13 @@
 	 * test expectation */
 	f_check_mgcp_expectations()
 
+	var RSL_Message chan_act := f_rslem_get_last_act(RSL1_PROC, 0, g_chan_nr);
+
 	/* Ensure the Channel Activation for the new channel contained the right encryption params. as_handover() set
 	 * g_chan_nr to the new lchan that was handed over to. It lives in bts 1, so look it up at RSL1_PROC. */
-	f_verify_encr_info(f_rslem_get_last_act(RSL1_PROC, 0, g_chan_nr));
+	f_verify_encr_info(chan_act);
+
+	f_chan_act_verify_tsc(chan_act, BTS_TSC[1]);
 
 	f_sleep(0.5);
 }
@@ -5116,6 +5120,8 @@
 	f_init(2, true);
 	f_sleep(1.0);
 
+	pars.expect_tsc := BTS_TSC[0];
+
 	f_ctrs_bsc_and_bts_init();
 
 	vc_conn := f_start_handler(refers(f_tc_ho_int), pars);