block: use blk_rq_init() to initialize the request

Any path needs to call it 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>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
diff --git a/drivers/scsi/scsi_error.c b/drivers/scsi/scsi_error.c
index 221f31e..1eaba6c 100644
--- a/drivers/scsi/scsi_error.c
+++ b/drivers/scsi/scsi_error.c
@@ -1771,6 +1771,7 @@
 	unsigned long flags;
 	int rtn;
 
+	blk_rq_init(NULL, &req);
 	scmd->request = &req;
 	memset(&scmd->eh_timeout, 0, sizeof(scmd->eh_timeout));