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/python-modules/cairosvg/default.nix

@@ -0,0 +1,51 @@
+{ lib
+, buildPythonPackage
+, fetchPypi
+, isPy3k
+, cairocffi
+, cssselect2
+, defusedxml
+, pillow
+, tinycss2
+, pytestCheckHook
+}:
+
+buildPythonPackage rec {
+  pname = "CairoSVG";
+  version = "2.5.2";
+  disabled = !isPy3k;
+
+  src = fetchPypi {
+    inherit pname version;
+    sha256 = "sha256-sLmSnPXboAUXjXRqgDb88AJVUPSYylTbYYczIjhHg7w=";
+  };
+
+  propagatedBuildInputs = [ cairocffi cssselect2 defusedxml pillow tinycss2 ];
+
+  propagatedNativeBuildInputs = [ cairocffi ];
+
+  checkInputs = [ pytestCheckHook ];
+
+  postPatch = ''
+    substituteInPlace setup.cfg \
+      --replace "pytest-runner" "" \
+      --replace "pytest-flake8" "" \
+      --replace "pytest-isort" "" \
+      --replace "pytest-cov" "" \
+      --replace "--flake8" "" \
+      --replace "--isort" ""
+  '';
+
+  pytestFlagsArray = [
+    "cairosvg/test_api.py"
+  ];
+
+  pythonImportsCheck = [ "cairosvg" ];
+
+  meta = with lib; {
+    homepage = "https://cairosvg.org";
+    license = licenses.lgpl3Plus;
+    description = "SVG converter based on Cairo";
+    maintainers = with maintainers; [ SuperSandro2000 ];
+  };
+}