direnv.nix-direnv: remove enableFlakes (nix-community#2458)

Since NixOS/nixpkgs#144197 flake support is
always available. The upstream `enableFlakes` option is scheduled to be
removed altogether in NixOS/nixpkgs#145236

modules/programs/direnv.nix

@@ -15,6 +15,8 @@ in {
       "direnv"
       "enableNixDirenvIntegration"
     ] [ "programs" "direnv" "nix-direnv" "enable" ])
+    (mkRemovedOptionModule [ "programs" "direnv" "nix-direnv" "enableFlakes" ]
+      "Flake support is now always enabled.")
   ];
 
   meta.maintainers = [ maintainers.rycee ];
@@ -79,7 +81,6 @@ in {
         <link
             xlink:href="https://github.com/nix-community/nix-direnv">nix-direnv</link>,
             a fast, persistent use_nix implementation for direnv'';
-      enableFlakes = mkEnableOption "Flake support in nix-direnv";
     };
 
   };
@@ -92,11 +93,9 @@ in {
     };
 
     xdg.configFile."direnv/direnvrc" = let
-      package =
-        pkgs.nix-direnv.override { inherit (cfg.nix-direnv) enableFlakes; };
       text = concatStringsSep "\n" (optional (cfg.stdlib != "") cfg.stdlib
         ++ optional cfg.nix-direnv.enable
-        "source ${package}/share/nix-direnv/direnvrc");
+        "source ${pkgs.nix-direnv}/share/nix-direnv/direnvrc");
     in mkIf (text != "") { inherit text; };
 
     programs.bash.initExtra = mkIf cfg.enableBashIntegration (