bts: Fix TC_rll_rel_req()

The test case was broken (c/r bit), the BTS operated correctly.

Change-Id: I07285aa715fa218c62b9fd2d81c88e73a4117f08
diff --git a/bts/BTS_Tests.ttcn b/bts/BTS_Tests.ttcn
index 69f7b57..49bf45e 100644
--- a/bts/BTS_Tests.ttcn
+++ b/bts/BTS_Tests.ttcn
@@ -3373,7 +3373,7 @@
 	RSL.send(ts_RSL_REL_REQ(g_chan_nr, tc.link_id, RSL_REL_MODE_NORMAL));
 	/* ... and expect the DISC on the Um side */
 	alt {
-	[] as_l1_exp_lapdm(tr_LAPDm_DISC(tc.sapi, cr_MO_CMD, true))  {
+	[] as_l1_exp_lapdm(tr_LAPDm_DISC(tc.sapi, cr_MT_CMD, true))  {
 		/* FIXME: send a UA in resposne to the DISC */
 		}
 	}