[PATCH] Convert users to tty_unregister_ldisc()

tty_register_ldisc(N_FOO, NULL) => tty_unregister_ldisc(N_FOO)

Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
diff --git a/drivers/input/serio/serport.c b/drivers/input/serio/serport.c
index f6b8522..79ca384 100644
--- a/drivers/input/serio/serport.c
+++ b/drivers/input/serio/serport.c
@@ -257,7 +257,7 @@
 
 static void __exit serport_exit(void)
 {
-	tty_register_ldisc(N_MOUSE, NULL);
+	tty_unregister_ldisc(N_MOUSE);
 }
 
 module_init(serport_init);