git-submodule: remove unused is_zero_oid() function

The is_zero_oid() function in git-submodule.sh has not been used since
e83e3333b57 (submodule: port submodule subcommand 'summary' from shell
to C, 2020-08-13), so we can remove it.

This was the last user of the sane_egrep() function in
git-sh-setup.sh. I'm not removing it in case some out-of-tree user
relied on it. Per the discussion that can be found upthread of [1].

1. https://lore.kernel.org/git/87tuiwjfvi.fsf@evledraar.gmail.com/

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

0 files changed, 0 insertions, 0 deletions