[SG] Update drivers to use sg helpers

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
diff --git a/drivers/usb/core/message.c b/drivers/usb/core/message.c
index 8dd5a6a..90d64a8 100644
--- a/drivers/usb/core/message.c
+++ b/drivers/usb/core/message.c
@@ -437,13 +437,11 @@
 #if defined(CONFIG_HIGHMEM) || defined(CONFIG_IOMMU)
 			io->urbs[i]->transfer_buffer = NULL;
 #else
-			io->urbs[i]->transfer_buffer =
-				page_address(sg[i].page) + sg[i].offset;
+			io->urbs[i]->transfer_buffer = sg_virt(&sg[i]);
 #endif
 		} else {
 			/* hc may use _only_ transfer_buffer */
-			io->urbs [i]->transfer_buffer =
-				page_address (sg [i].page) + sg [i].offset;
+			io->urbs [i]->transfer_buffer = sg_virt(&sg[i]);
 			len = sg [i].length;
 		}