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/x11/fractalart.nix

@@ -0,0 +1,36 @@
+{ config, lib, pkgs, ... }:
+with lib;
+let
+  cfg = config.services.fractalart;
+in {
+  options.services.fractalart = {
+    enable = mkOption {
+      type = types.bool;
+      default = false;
+      example = true;
+      description = "Enable FractalArt for generating colorful wallpapers on login";
+    };
+
+    width = mkOption {
+      type = types.nullOr types.int;
+      default = null;
+      example = 1920;
+      description = "Screen width";
+    };
+
+    height = mkOption {
+      type = types.nullOr types.int;
+      default = null;
+      example = 1080;
+      description = "Screen height";
+    };
+  };
+
+  config = mkIf cfg.enable {
+    environment.systemPackages = [ pkgs.haskellPackages.FractalArt ];
+    services.xserver.displayManager.sessionCommands =
+      "${pkgs.haskellPackages.FractalArt}/bin/FractalArt --no-bg -f .background-image"
+        + optionalString (cfg.width  != null) " -w ${toString cfg.width}"
+        + optionalString (cfg.height != null) " -h ${toString cfg.height}";
+  };
+}