scsi: missing add of padded bytes to io completion byte count

Original patch from Tejun Heo <htejun@gmail.com> but should use ->extra_len
and not ->data_len, as we would then overshoot the original request size.

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>

drivers/scsi/scsi.c

@@ -757,7 +757,7 @@ void scsi_finish_command(struct scsi_cmnd *cmd)
 				"Notifying upper driver of completion "
 				"(result %x)\n", cmd->result));
 
-	good_bytes = scsi_bufflen(cmd);
+	good_bytes = scsi_bufflen(cmd) + cmd->request->extra_len;
         if (cmd->request->cmd_type != REQ_TYPE_BLOCK_PC) {
 		drv = scsi_cmd_to_driver(cmd);
 		if (drv->done)