Merge branch 'jk/ewah-bounds-check'

The code to read compressed bitmap was not careful to avoid reading
past the end of the file, which has been corrected.

* jk/ewah-bounds-check:
  ewah: adjust callers of ewah_read_mmap()
  ewah_read_mmap: bounds-check mmap reads

diff --cc dir.c
Simple merge

diff --cc pack-bitmap.c
Simple merge

diff --cc t/t5310-pack-bitmaps.sh
Simple merge