ns proc: Add support for the ipc namespace

Acked-by: Daniel Lezcano <daniel.lezcano@free.fr>
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>

fs/proc/namespaces.c

@@ -22,6 +22,9 @@ static const struct proc_ns_operations *ns_entries[] = {
 #ifdef CONFIG_UTS_NS
 	&utsns_operations,
 #endif
+#ifdef CONFIG_IPC_NS
+	&ipcns_operations,
+#endif
 };
 
 static const struct file_operations ns_file_operations = {