[PATCH] remove dead code from elevator switching

We already drop the refcount in elevator_exit(), and as
we're setting 'e' to NULL, we'll never take that branch anyway.
Finally, as 'e' is a local var that isn't referenced afterwards,
setting it to NULL is pointless.
Signed-off-by: NDave Jones <davej@redhat.com>
Signed-off-by: NJens Axboe <axboe@suse.de>

block/elevator.c

@@ -850,12 +850,9 @@ static int elevator_switch(request_queue_t *q, struct elevator_type *new_e)
 	 * one again (along with re-adding the sysfs dir)
 	 */
 	elevator_exit(e);
-	e = NULL;
 	q->elevator = old_elevator;
 	elv_register_queue(q);
 	clear_bit(QUEUE_FLAG_ELVSWITCH, &q->queue_flags);
-	if (e)
-		kobject_put(&e->kobj);
 	return 0;
 }