dir: check pathspecs before returning `path_excluded`

dir: check pathspecs before returning `path_excluded`

In 95c11ecc73 ("Fix error-prone fill_directory() API; make it only
return matches", 2020-04-01), we taught `fill_directory()`, or more
specifically `treat_path()`, to check against any pathspecs so that we
could simplify the callers.

But in doing so, we added a slightly-too-early return for the "excluded"
case. We end up not checking the pathspecs, meaning we return
`path_excluded` when maybe we should return `path_none`. As a result,
`git status --ignored -- pathspec` might show paths that don't actually
match "pathspec".

Move the "excluded" check down to after we've checked any pathspecs.

Reported-by: Andreas Schwab <redacted>
Reviewed-by: Elijah Newren <redacted>
Signed-off-by: Martin Ågren <redacted>
Signed-off-by: Junio C Hamano <redacted>