bsc_api: Send RR Release and de-activate the SACCH on error

In case the connection should not be created/accepted release
the channel by sending a RR Release and de-activating the
SACCH. Phones should deal better with that behavior.
diff --git a/openbsc/src/libbsc/bsc_api.c b/openbsc/src/libbsc/bsc_api.c
index 95b418b..a451e05 100644
--- a/openbsc/src/libbsc/bsc_api.c
+++ b/openbsc/src/libbsc/bsc_api.c
@@ -618,7 +618,7 @@
 		rc = BSC_API_CONN_POL_REJECT;
 		lchan->conn = subscr_con_allocate(msg->lchan);
 		if (!lchan->conn) {
-			lchan_release(lchan, 0, 0);
+			lchan_release(lchan, 1, 0);
 			return -1;
 		}
 
@@ -628,7 +628,7 @@
 		if (rc != BSC_API_CONN_POL_ACCEPT) {
 			lchan->conn->lchan = NULL;
 			subscr_con_free(lchan->conn);
-			lchan_release(lchan, 0, 0);
+			lchan_release(lchan, 1, 0);
 		}
 	}