bts: Add TC_deact_sacch()

This test case checks on each logical channel if the DEACT SACCH RSL
message actually deactivates downlink SACCH as expected.

Change-Id: Id8219ffce0635071cb50669b89368de51fe82843
diff --git a/library/L1CTL_Types.ttcn b/library/L1CTL_Types.ttcn
index 814e7df..d883a22 100644
--- a/library/L1CTL_Types.ttcn
+++ b/library/L1CTL_Types.ttcn
@@ -609,7 +609,9 @@
 	/* for matching against incoming DATA_IND */
 	template L1ctlDlMessage tr_L1CTL_DATA_IND(template RslChannelNr chan_nr,
 						 template RslLinkId link_id := ?,
-						 template octetstring l2_data := ?) := {
+						 template octetstring l2_data := ?,
+						 template uint8_t num_biterr := 0,
+						 template uint8_t fire_crc := 0) := {
 		header := tr_L1ctlHeader(L1CTL_DATA_IND),
 		dl_info := {
 			chan_nr := chan_nr,
@@ -618,8 +620,8 @@
 			frame_nr := ?,
 			rx_level := ?,
 			snr := ?,
-			num_biterr := ?,
-			fire_crc := ?
+			num_biterr := num_biterr,
+			fire_crc := fire_crc 
 		},
 		payload := {
 			data_ind := {