Add name_lookup function in object_ops.

diff --git a/server/serial.c b/server/serial.c
index e2763dc..09ca6ec 100644
--- a/server/serial.c
+++ b/server/serial.c
@@ -100,6 +100,7 @@
     no_satisfied,                 /* satisfied */
     no_signal,                    /* signal */
     serial_get_fd,                /* get_fd */
+    no_lookup_name,               /* lookup_name */
     no_close_handle,              /* close_handle */
     serial_destroy                /* destroy */
 };