reflog expire: don't use lookup_commit_reference_gently()
In the initial implementation of "git reflog" in 4264dc15e19 (git reflog expire, 2006-12-19) we had this lookup_commit_reference_gently(). I don't think we've ever found tags that we need to recursively dereference in reflogs, so this should at least be changed to a "lookup commit" as I'm doing here, although I can't think of a way where it mattered in practice. I also think we'd probably like to just die here if we have a NULL object, but as this code needs to handle potentially broken repositories let's just show an "error" but continue, the non-quiet lookup_commit() will do for us. None of our tests cover the case where "commit" is NULL after this lookup. Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>