Merge branch 'tb/midx-repack-ignore-cruft-packs'

"git multi-pack-index repack/expire" used to repack unreachable cruft into a new pack, which have been corrected. * tb/midx-repack-ignore-cruft-packs: midx.c: avoid cruft packs with non-zero `repack --batch-size` midx.c: remove unnecessary loop condition midx.c: replace `xcalloc()` with `CALLOC_ARRAY()` midx.c: avoid cruft packs with `repack --batch-size=0` midx.c: prevent `expire` from removing the cruft pack Documentation/git-multi-pack-index.txt: clarify expire behavior Documentation/git-multi-pack-index.txt: fix typo