[BLOCK] Get rid of request_queue_t typedef

Some of the code has been gradually transitioned to using the proper
struct request_queue, but there's lots left. So do a full sweet of
the kernel and get rid of this typedef and replace its uses with
the proper type.

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
diff --git a/drivers/block/viodasd.c b/drivers/block/viodasd.c
index dae3991..85916e2 100644
--- a/drivers/block/viodasd.c
+++ b/drivers/block/viodasd.c
@@ -400,7 +400,7 @@
 /*
  * This is the external request processing routine
  */
-static void do_viodasd_request(request_queue_t *q)
+static void do_viodasd_request(struct request_queue *q)
 {
 	struct request *req;