/usr/share/doc/libcephfs-dev/changelog.Debian.gz is in libcephfs-dev 0.79-0ubuntu1.
This file is owned by root:root, with mode 0o777.
It is a symlink to /usr/share/doc/libcephfs-dev/../libcephfs1/changelog.Debian.gz
/usr/share/doc/libcephfs-dev/../libcephfs1/changelog.Debian.gz