uboot: (firmwareOdroidC2/C4) don't invoke patch tool, use patches = [] instead

https://github.com/NixOS/nixpkgs/blob/master/pkgs/stdenv/generic/setup.sh#L948
this can do it nicely.

Signed-off-by: Anton Arapov <anton@deadbeef.mx>

nixos/modules/services/misc/ihaskell.nix

@@ -0,0 +1,65 @@
+{ pkgs, lib, config, ... }:
+
+with lib;
+
+let
+
+  cfg = config.services.ihaskell;
+  ihaskell = pkgs.ihaskell.override {
+    packages = cfg.extraPackages;
+  };
+
+in
+
+{
+  options = {
+    services.ihaskell = {
+      enable = mkOption {
+        type = types.bool;
+        default = false;
+        description = "Autostart an IHaskell notebook service.";
+      };
+
+      extraPackages = mkOption {
+        type = types.functionTo (types.listOf types.package);
+        default = haskellPackages: [];
+        defaultText = literalExpression "haskellPackages: []";
+        example = literalExpression ''
+          haskellPackages: [
+            haskellPackages.wreq
+            haskellPackages.lens
+          ]
+        '';
+        description = ''
+          Extra packages available to ghc when running ihaskell. The
+          value must be a function which receives the attrset defined
+          in <varname>haskellPackages</varname> as the sole argument.
+        '';
+      };
+    };
+  };
+
+  config = mkIf cfg.enable {
+
+    users.users.ihaskell = {
+      group = config.users.groups.ihaskell.name;
+      description = "IHaskell user";
+      home = "/var/lib/ihaskell";
+      createHome = true;
+      uid = config.ids.uids.ihaskell;
+    };
+
+    users.groups.ihaskell.gid = config.ids.gids.ihaskell;
+
+    systemd.services.ihaskell = {
+      description = "IHaskell notebook instance";
+      wantedBy = [ "multi-user.target" ];
+      after = [ "network.target" ];
+      serviceConfig = {
+        User = config.users.users.ihaskell.name;
+        Group = config.users.groups.ihaskell.name;
+        ExecStart = "${pkgs.runtimeShell} -c \"cd $HOME;${ihaskell}/bin/ihaskell-notebook\"";
+      };
+    };
+  };
+}