unregister_chrdev(): ignore the return value

unregister_chrdev() always returns 0.  There is no need to check the return
value.

Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/drivers/char/mbcs.c b/drivers/char/mbcs.c
index 57f9115..3daf5e0 100644
--- a/drivers/char/mbcs.c
+++ b/drivers/char/mbcs.c
@@ -816,12 +816,7 @@
 
 static void __exit mbcs_exit(void)
 {
-	int rv;
-
-	rv = unregister_chrdev(mbcs_major, DEVICE_NAME);
-	if (rv < 0)
-		DBG(KERN_ALERT "Error in unregister_chrdev: %d\n", rv);
-
+	unregister_chrdev(mbcs_major, DEVICE_NAME);
 	cx_driver_unregister(&mbcs_driver);
 }