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/plotinus.nix

@@ -0,0 +1,28 @@
+import ./make-test-python.nix ({ pkgs, ... }: {
+  name = "plotinus";
+  meta = {
+    maintainers = pkgs.plotinus.meta.maintainers;
+  };
+
+  nodes.machine =
+    { pkgs, ... }:
+
+    { imports = [ ./common/x11.nix ];
+      programs.plotinus.enable = true;
+      environment.systemPackages = [ pkgs.gnome.gnome-calculator pkgs.xdotool ];
+    };
+
+  testScript = ''
+    machine.wait_for_x()
+    machine.succeed("gnome-calculator >&2 &")
+    machine.wait_for_window("gnome-calculator")
+    machine.succeed(
+        "xdotool search --sync --onlyvisible --class gnome-calculator "
+        + "windowfocus --sync key --clearmodifiers --delay 1 'ctrl+shift+p'"
+    )
+    machine.sleep(5)  # wait for the popup
+    machine.succeed("xdotool key --delay 100 p r e f e r e n c e s Return")
+    machine.wait_for_window("Preferences")
+    machine.screenshot("screen")
+  '';
+})