block: rename BLK_EH_NOT_HANDLED to BLK_EH_DONE

The BLK_EH_NOT_HANDLED implies nothing happen, but very often that
is not what is happening - instead the driver already completed the
command.  Fix the symbolic name to reflect that a little better.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
diff --git a/drivers/block/nbd.c b/drivers/block/nbd.c
index 800e1ec..88ae833 100644
--- a/drivers/block/nbd.c
+++ b/drivers/block/nbd.c
@@ -332,7 +332,7 @@ static enum blk_eh_timer_return nbd_xmit_timeout(struct request *req,
 			}
 			blk_mq_requeue_request(req, true);
 			nbd_config_put(nbd);
-			return BLK_EH_NOT_HANDLED;
+			return BLK_EH_DONE;
 		}
 	} else {
 		dev_err_ratelimited(nbd_to_dev(nbd),