[BLOCK] Cleanup unused variable passing

[BLOCK] Cleanup unused variable passing

- ->init_queue() does not need the elevator passed in
- ->put_request() is a hot path and need not have the queue passed in
- cfq_update_io_seektime() does not need cfqd passed in

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>