bsc: handover: actually send Handover Detect

Until now, the test went from RR Handover Command directly to RR Handover
Complete, and osmo-bsc didn't mind it. However, the normal handover procedure
requires an RSL Handover Detect to be sent in-between those. Send that.

Change-Id: I6e54edcc3a99e116d852eca8e48c7a5bc685e832
diff --git a/library/RSL_Types.ttcn b/library/RSL_Types.ttcn
index 3804d40..e1f6af0 100644
--- a/library/RSL_Types.ttcn
+++ b/library/RSL_Types.ttcn
@@ -1309,6 +1309,15 @@
 		}
 	}
 
+	/* 8.4.7 BTS -> BSC */
+	template (value) RSL_Message ts_RSL_HANDO_DET(template (value) RslChannelNr chan_nr) := {
+		msg_disc := ts_RSL_MsgDisc(RSL_MDISC_DCHAN, false),
+		msg_type := RSL_MT_HANDO_DET,
+		ies := {
+			t_RSL_IE(RSL_IE_CHAN_NR, RSL_IE_Body:{chan_nr := chan_nr})
+		}
+	}
+
 
 	/* COMMON CHANNEL MANAGEMENT MESSAGES */