mq-deadline: add 'deadline' as a name alias

The scheduler framework now supports looking up the appropriate
scheduler with the {name,mq} tupple. We can register mq-deadline
with the alias of 'deadline', so that switching to 'deadline'
will do the right thing based on the type of driver attached to
it.
Reviewed-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

block/mq-deadline.c

@@ -657,6 +657,7 @@ static struct elevator_type mq_deadline = {
 #endif
 	.elevator_attrs = deadline_attrs,
 	.elevator_name = "mq-deadline",
+	.elevator_alias = "deadline",
 	.elevator_owner = THIS_MODULE,
 };
 MODULE_ALIAS("mq-deadline-iosched");