block, scsi: move the retries field to struct scsi_request

Instead of bloating the generic struct request with it.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Jens Axboe <axboe@fb.com>
diff --git a/include/scsi/scsi_request.h b/include/scsi/scsi_request.h
index ba0aeb9..7c583a0 100644
--- a/include/scsi/scsi_request.h
+++ b/include/scsi/scsi_request.h
@@ -11,6 +11,7 @@
 	unsigned short	cmd_len;
 	unsigned int	sense_len;
 	unsigned int	resid_len;	/* residual count */
+	int		retries;
 	void		*sense;
 };