/usr/lib/ghc-doc/hoogle/libghc-cmdargs-doc.txt is in libghc-cmdargs-doc 0.10.13-4.
This file is owned by root:root, with mode 0o777.
It is a symlink to /usr/lib/ghc-doc/hoogle/../../../share/doc/libghc-cmdargs-doc/html/cmdargs.txt