ide: use blk_rq_init() to initialize the request

This converts ide to use blk_rq_init to initialize the request.

This is a preparation for large command support, which needs to
initialize the request in a proper way (that is, just doing a memset()
will not work).

Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Cc: Jens Axboe <jens.axboe@oracle.com>
Cc: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
diff --git a/drivers/ide/ide-taskfile.c b/drivers/ide/ide-taskfile.c
index 9a846a0..0c908ca 100644
--- a/drivers/ide/ide-taskfile.c
+++ b/drivers/ide/ide-taskfile.c
@@ -494,8 +494,7 @@
 {
 	struct request rq;
 
-	memset(&rq, 0, sizeof(rq));
-	rq.ref_count = 1;
+	blk_rq_init(NULL, &rq);
 	rq.cmd_type = REQ_TYPE_ATA_TASKFILE;
 	rq.buffer = buf;