sd: Move scsi_disk() accessor function to sd.h

Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

---

diff --git a/drivers/scsi/sd.c b/drivers/scsi/sd.c
--- a/drivers/scsi/sd.c
+++ b/drivers/scsi/sd.c
@@ -293,11 +293,6 @@ static int sd_major(int major_idx)
 		BUG();
 		return 0;	/* shut up gcc */
 	}
-}
-
-static inline struct scsi_disk *scsi_disk(struct gendisk *disk)
-{
-	return container_of(disk->private_data, struct scsi_disk, driver);
 }
 
 static struct scsi_disk *__scsi_disk_get(struct gendisk *disk)
diff --git a/drivers/scsi/sd.h b/drivers/scsi/sd.h
--- a/drivers/scsi/sd.h
+++ b/drivers/scsi/sd.h
@@ -48,6 +48,11 @@ struct scsi_disk {
 };
 #define to_scsi_disk(obj) container_of(obj,struct scsi_disk,dev)
 
+static inline struct scsi_disk *scsi_disk(struct gendisk *disk)
+{
+	return container_of(disk->private_data, struct scsi_disk, driver);
+}
+
 #define sd_printk(prefix, sdsk, fmt, a...)				\
         (sdsk)->disk ?							\
 	sdev_printk(prefix, (sdsk)->device, "[%s] " fmt,		\