setup: inline `check_and_apply_repository_format()`

setup: inline `check_and_apply_repository_format()`

We have two callsites of `check_and_apply_repository_format()`. In a
subsequent commit we'll want to adapt one of those callsites to change
the order in which we read and apply the repository format, at which
point the helper function will not really be a good fit for us anymore.

Inline the function to both of the callsites.

Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>