/usr/lib/ghc-doc/hoogle/HaXml.txt is in libghc-haxml-doc 1:1.23.3-2build1.
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
/usr/lib/ghc-doc/hoogle/../../../share/doc/libghc-haxml-doc/html/HaXml.txt