btrfs: insert newly opened device to the end of the list

Add opened device to the tail of dev_alloc_list instead of head, so that
it maintains the same order as dev_list.
Signed-off-by: NAnand Jain <anand.jain@oracle.com>
Reviewed-by: NNikolay Borisov <nborisov@suse.com>
Signed-off-by: NDavid Sterba <dsterba@suse.com>

fs/btrfs/volumes.c

@@ -709,7 +709,7 @@ static int btrfs_open_one_device(struct btrfs_fs_devices *fs_devices,
 	if (test_bit(BTRFS_DEV_STATE_WRITEABLE, &device->dev_state) &&
 	    device->devid != BTRFS_DEV_REPLACE_DEVID) {
 		fs_devices->rw_devices++;
-		list_add(&device->dev_alloc_list, &fs_devices->alloc_list);
+		list_add_tail(&device->dev_alloc_list, &fs_devices->alloc_list);
 	}
 	brelse(bh);