/usr/share/doc/libicestorm35/changelog.Debian.gz is in libicestorm35 3.5.1-5.2.
This file is owned by root:root, with mode 0o777.
It is a symlink to /usr/share/doc/libicestorm35/../libfreeze35/changelog.Debian.gz
/usr/share/doc/libicestorm35/../libfreeze35/changelog.Debian.gz