repack: unconditionally exclude non-kept packs
In `write_cruft_pack()`, we handle excluding objects found in non-kept packs from being included in the cruft pack via two code paths: * When using '--combine-cruft-below-size' (provided that we are not expiring cruft objects), we use the aptly-named `combine_small_cruft_packs()` function. * In all other cases, we handle it directly in the 'else' branch of the same conditional. Simplify this by moving the non-kept pack exclusion out of the conditional entirely, so that non-kept packs are always excluded regardless of whether we are combining small cruft packs or not. This is a preparatory refactor for a subsequent change that will use the pack_geometry struct when available to determine which non-kept packs to exclude. Signed-off-by: Taylor Blau <me@ttaylorr.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>