nixpkgs: Always set nixpkgs.config.{state,store}Dir
nixpkgs: Always set nixpkgs.config.{state,store}Dir

This will allow NixOS modules to always refer to config.nixpkgs.config.nix to find the store or state
directory

git-svn-id: 71c8032c709790ec749031c4215f8515ac00dc5a@30103 70bd8c7a-acb8-0310-9f0d-9cc1c95dcdbb

falsifian/personal_nixos,falsifian/personal_nixos,falsifian/personal_nixos,falsifian/personal_nixos,falsifian/personal_nixos