/usr/lib/ghc-doc/hoogle/primes.txt is in libghc-primes-doc 0.2.1.0-4.
This file is owned by root:root, with mode 0o777.
It is a symlink to /usr/lib/ghc-doc/hoogle/../../../share/doc/libghc-primes-doc/html/primes.txt
/usr/lib/ghc-doc/hoogle/../../../share/doc/libghc-primes-doc/html/primes.txt