/usr/lib/ghc-doc/hoogle/libghc-diagrams-svg-doc.txt is in libghc-diagrams-svg-doc 1.4.0.3-2.
This file is owned by root:root, with mode 0o777.
It is a symlink to /usr/lib/ghc-doc/hoogle/../../../share/doc/libghc-diagrams-svg-doc/html/diagrams-svg.txt