[SG] Update drivers to use sg helpers

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
diff --git a/drivers/scsi/sun3_NCR5380.c b/drivers/scsi/sun3_NCR5380.c
index 4aafe89..2dcde37 100644
--- a/drivers/scsi/sun3_NCR5380.c
+++ b/drivers/scsi/sun3_NCR5380.c
@@ -272,8 +272,7 @@
 #define	HOSTNO		instance->host_no
 #define	H_NO(cmd)	(cmd)->device->host->host_no
 
-#define SGADDR(buffer) (void *)(((unsigned long)page_address((buffer)->page)) + \
-			(buffer)->offset)
+#define SGADDR(buffer) (void *)(((unsigned long)sg_virt(((buffer)))))
 
 #ifdef SUPPORT_TAGS