Remove added attributes

ghcjs should have everything it needs & we can handle this all in Nixpkgs.

default.nix

@@ -162,17 +162,7 @@ let overrideCabal = pkg: f: if pkg == null then null else haskellLib.overrideCab
     ghcjsPkgs = ghcjs: self: super: {
       ghcjs = ghcjs.overrideAttrs (o: {
         patches = (o.patches or []) ++ optional useFastWeak ./fast-weak.patch;
-      }) // {
-        bootPkgs = ghc8_2_2;
-        isGhcjs = true;
-        stage1Packages = []; #TODO
-        mkStage2 = _: {};
-        meta.platforms = self.ghc.meta.platforms;
-        version = ghcjs.version;
-        targetPrefix = "";
-        haskellCompilerName = "ghcjs";
-        socket-io = nixpkgs.nodePackages."socket.io";
-      };
+      });
       ghci-ghcjs = self.callCabal2nix "ghci-ghcjs" (ghcjsSrc + "/lib/ghci-ghcjs") {};
       ghcjs-th = self.callCabal2nix "ghcjs-th" (ghcjsSrc + "/lib/ghcjs-th") {};
       template-haskell-ghcjs = self.callCabal2nix "template-haskell-ghcjs" (ghcjsSrc + "/lib/template-haskell-ghcjs") {};