Input: handle serio_register_driver() errors

Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>
diff --git a/drivers/input/keyboard/xtkbd.c b/drivers/input/keyboard/xtkbd.c
index b53f716..a820934 100644
--- a/drivers/input/keyboard/xtkbd.c
+++ b/drivers/input/keyboard/xtkbd.c
@@ -174,8 +174,7 @@
 
 static int __init xtkbd_init(void)
 {
-	serio_register_driver(&xtkbd_drv);
-	return 0;
+	return serio_register_driver(&xtkbd_drv);
 }
 
 static void __exit xtkbd_exit(void)