D4710: lfs: add repository feature denoting the use of LFS

[Yuya Nishihara]

> +    wrapfunction(localrepo, 'makefilestorage', wrapper.localrepomakefilestorage)

As I pointed out before, `makefilestorage` can't be wrapped in this way
because it's captured as `REPO_INTERFACES[1][1]` earlier. The easiest
workaround I can think of is to wrap the reference in `REPO_INTERFACES`
with lambda, so the `makefilestorage` is looked up by name every time.