/usr/share/doc/libghc-bytestring-mmap-prof/changelog.Debian.gz is in libghc-bytestring-mmap-prof 0.2.2-8.
This file is owned by root:root, with mode 0o777.
It is a symlink to /usr/share/doc/libghc-bytestring-mmap-prof/../libghc-bytestring-mmap-dev/changelog.Debian.gz