Status() in a repo with LFS files reports all LFS files as modified

[sambonfire]

Simple programming just running this on my repo that has many LFS files in it:

	r, err := git.PlainOpen(*folder)
	CheckIfError(err)

	w, err := r.Worktree()
	CheckIfError(err)

	status, err := w.Status()

It reports all the LFS files as being modified.

It's also incredibly slow, but it looks like that's been captured in other reported issues.

[ImJeremyHe]

I met this problem too. All I want it to get the files to be committed. w.Status() gets LFS files and it took time to iterate them.

[cblomart]

Is this the same issue as #918 ?