structured-haskell-mode: update post-process hook to install both the *.el and *.elc files
structured-haskell-mode: update post-process hook to install both the *.el and *.elc files

Taken from <https://github.com/NixOS/nixpkgs/pull/2083>.

spencerjanssen/cabal2nix,jb55/cabal2nix,dmalikov/cabal2nix,gridaphobe/cabal2nix,Fuuzetsu/cabal2nix,bennofs/cabal2nix,psibi/cabal2nix