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/tests/xfce.nix

@@ -0,0 +1,45 @@
+import ./make-test-python.nix ({ pkgs, ...} : {
+  name = "xfce";
+
+  nodes.machine =
+    { pkgs, ... }:
+
+    {
+      imports = [
+        ./common/user-account.nix
+      ];
+
+      services.xserver.enable = true;
+
+      services.xserver.displayManager = {
+        lightdm.enable = true;
+        autoLogin = {
+          enable = true;
+          user = "alice";
+        };
+      };
+
+      services.xserver.desktopManager.xfce.enable = true;
+
+      hardware.pulseaudio.enable = true; # needed for the factl test, /dev/snd/* exists without them but udev doesn't care then
+
+    };
+
+  testScript = { nodes, ... }: let
+    user = nodes.machine.config.users.users.alice;
+  in ''
+      machine.wait_for_x()
+      machine.wait_for_file("${user.home}/.Xauthority")
+      machine.succeed("xauth merge ${user.home}/.Xauthority")
+      machine.wait_for_window("xfce4-panel")
+      machine.sleep(10)
+
+      # Check that logging in has given the user ownership of devices.
+      machine.succeed("getfacl -p /dev/snd/timer | grep -q ${user.name}")
+
+      machine.succeed("su - ${user.name} -c 'DISPLAY=:0.0 xfce4-terminal >&2 &'")
+      machine.wait_for_window("Terminal")
+      machine.sleep(10)
+      machine.screenshot("screen")
+    '';
+})