[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>

drivers/net/irda/irtty-sir.c

@@ -626,7 +626,7 @@ static void __exit irtty_sir_cleanup(void)
 {
 	int err;
 
-	if ((err = tty_register_ldisc(N_IRDA, NULL))) {
+	if ((err = tty_unregister_ldisc(N_IRDA))) {
 		IRDA_ERROR("%s(), can't unregister line discipline (err = %d)\n",
 			   __FUNCTION__, err);
 	}