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>

pkgs/tools/security/badchars/default.nix

@@ -0,0 +1,32 @@
+{ lib
+, buildPythonApplication
+, fetchPypi
+}:
+
+buildPythonApplication rec {
+  pname = "badchars";
+  version = "0.4.0";
+
+  src = fetchPypi {
+    inherit pname version;
+    sha256 = "1xqki8qnfwl97d60xj69alyzwa1mnfbwki25j0vhvhb05varaxz2";
+  };
+
+  postPatch = ''
+    substituteInPlace setup.py --replace "argparse" ""
+  '';
+
+  # no tests are available and it can't be imported (it's only a script, not a module)
+  doCheck = false;
+
+  meta = with lib; {
+    description = "HEX badchar generator for different programming languages";
+    longDescription = ''
+      A HEX bad char generator to instruct encoders such as shikata-ga-nai to
+      transform those to other chars.
+    '';
+    homepage = "https://github.com/cytopia/badchars";
+    license = with licenses; [ mit ];
+    maintainers = with maintainers; [ fab ];
+  };
+}