/usr/share/doc/libnl-xfrm-3-200/changelog.Debian.gz is in libnl-xfrm-3-200 3.2.29-0ubuntu3.
This file is owned by root:root, with mode 0o777.
It is a symlink to /usr/share/doc/libnl-xfrm-3-200/../libnl-3-200/changelog.Debian.gz