bts: f_rsl_transceive: Add altsteps for sacch/facch/meas_rep

It may be that during CHAN DEACT we still receive any of those messages,
which is not an error condition.  Let's activate the related altsteps.

Change-Id: Ic27b28ead3fc4bff82655d0e8d88fda01b71eca7
diff --git a/bts/BTS_Tests.ttcn b/bts/BTS_Tests.ttcn
index 7b6fc2f..80500f2 100644
--- a/bts/BTS_Tests.ttcn
+++ b/bts/BTS_Tests.ttcn
@@ -379,6 +379,9 @@
 		setverdict(fail, "Timeout expecting " & id);
 		self.stop;
 		}
+	[] as_l1_sacch();
+	[] as_meas_res();
+	[] as_l1_dcch();
 	[] RSL.receive {
 		setverdict(fail, "Unexpected RSL message received");
 		}