/usr/lib/ghc-doc/hoogle/libghc-haxml-doc.txt is in libghc-haxml-doc 1:1.25.3-4build1.
This file is owned by root:root, with mode 0o777.
It is a symlink to /usr/lib/ghc-doc/hoogle/../../../share/doc/libghc-haxml-doc/html/HaXml.txt