iucs: Add a function to return the connection ID for the IU SCCP conn

Change-Id: Ica4a7f463fcf1bd67fe082296cecea8d10f2fc5b
diff --git a/src/libmsc/iucs.c b/src/libmsc/iucs.c
index 7bb45b2..d6da1f7 100644
--- a/src/libmsc/iucs.c
+++ b/src/libmsc/iucs.c
@@ -251,3 +251,7 @@
 	return 0;
 }
 
+uint32_t iu_get_conn_id(const struct ranap_ue_conn_ctx *ue)
+{
+	return ue->conn_id;
+}