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/development/libraries/py3c/default.nix

@@ -0,0 +1,38 @@
+{ lib, stdenv, fetchFromGitHub, python2, python3 }:
+
+stdenv.mkDerivation rec {
+  pname = "py3c";
+  version = "1.4";
+
+  src = fetchFromGitHub {
+    owner = "encukou";
+    repo = pname;
+    rev = "v${version}";
+    sha256 = "sha256-v8+0J56sZVbGdBlOotObUa10/zFMTvfXdMYRsKhyZaY=";
+  };
+
+  postPatch = ''
+    # clang and gcc-11 complain about 'register' keywords used by
+    # python-2.7. Let's avoid blanket -Werror.
+    substituteInPlace test/setup.py \
+      --replace "'-Werror', " ""
+  '';
+
+  makeFlags = [
+    "prefix=${placeholder "out"}"
+  ];
+
+  doCheck = true;
+
+  checkInputs = [
+    python2
+    python3
+  ];
+
+  meta = with lib; {
+    homepage = "https://github.com/encukou/py3c";
+    description = "Python 2/3 compatibility layer for C extensions";
+    license = licenses.mit;
+    maintainers = with maintainers; [ ajs124 dotlambda ];
+  };
+}