Merge branch 'tb/midx-write-propagate-namehash'

"git multi-pack-index write --bitmap" learns to propagate the hashcache from original bitmap to resulting bitmap. * tb/midx-write-propagate-namehash: t5326: test propagating hashcache values p5326: generate pack bitmaps before writing the MIDX bitmap p5326: don't set core.multiPackIndex unnecessarily p5326: create missing 'perf-tag' tag midx.c: respect 'pack.writeBitmapHashcache' when writing bitmaps pack-bitmap.c: propagate namehash values from existing bitmaps t/helper/test-bitmap.c: add 'dump-hashes' mode