Flags.hs: remove obsolete exceptions for xmonad-extras
Flags.hs: remove obsolete exceptions for xmonad-extras

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