/usr/share/doc/postgresql-9.5-postgis-2.2/NEWS.Debian.gz is in postgresql-9.5-postgis-2.2 2.2.1+dfsg-2.
This file is owned by root:root, with mode 0o777.
It is a symlink to /usr/share/doc/postgresql-9.5-postgis-2.2/../liblwgeom-2.2-5/NEWS.Debian.gz