fsck: sort files alphabetically again
fsck: sort files alphabetically again

This makes fsck runs deterministic again.

Sorting (commit quoted below) got lost while
moving to go-fuse v2 api.

commit e6caf56ea4ab10e747aa5dfc0a768cb8176ebe6a
Author: Jakob Unterwurzacher <jakobunt@gmail.com>
Date:   Mon Apr 2 16:56:29 2018 +0200

    fsck: sort files alphabetically

    This makes fsck runs deterministic.

rfjakob/gocryptfs,rfjakob/gocryptfs,rfjakob/gocryptfs,rfjakob/gocryptfs