osmo-bsc: Make it compile against paging_request_stop() api change

The additional msgb argument was introduced by Sylvain in
c7ff2572a723e6ace3006e6d7c77c0b19c0e0401
diff --git a/openbsc/src/bsc/osmo_bsc_filter.c b/openbsc/src/bsc/osmo_bsc_filter.c
index edd1b0d..edad38c 100644
--- a/openbsc/src/bsc/osmo_bsc_filter.c
+++ b/openbsc/src/bsc/osmo_bsc_filter.c
@@ -91,7 +91,7 @@
 		return -1;
 	}
 
-	paging_request_stop(conn->bts, subscr, conn);
+	paging_request_stop(conn->bts, subscr, conn, msg);
 	subscr_put(subscr);
 	return 0;
 }