block: let elv_register() return void

elv_register() always returns 0, and there isn't anything it does where
it should return an error (the only error condition is so grave that
it's handled with a BUG_ON).

Signed-off-by: Adrian Bunk <bunk@kernel.org>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
diff --git a/block/elevator.c b/block/elevator.c
index 446aea2..e452deb 100644
--- a/block/elevator.c
+++ b/block/elevator.c
@@ -960,7 +960,7 @@
 		__elv_unregister_queue(q->elevator);
 }
 
-int elv_register(struct elevator_type *e)
+void elv_register(struct elevator_type *e)
 {
 	char *def = "";
 
@@ -975,7 +975,6 @@
 				def = " (default)";
 
 	printk(KERN_INFO "io scheduler %s registered%s\n", e->elevator_name, def);
-	return 0;
 }
 EXPORT_SYMBOL_GPL(elv_register);