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/sphinxcontrib-tikz/default.nix

@@ -0,0 +1,38 @@
+{ lib
+, buildPythonPackage
+, fetchPypi
+, sphinx
+, pdf2svg
+, texLive
+}:
+
+buildPythonPackage rec {
+  pname = "sphinxcontrib-tikz";
+  version = "0.4.16";
+
+  src = fetchPypi {
+    inherit pname version;
+    sha256 = "sha256-8f9FNx6WMopcqihUzNlQoPBGYoW2YkFi6W1iaFLD4qU=";
+  };
+
+  postPatch = ''
+    substituteInPlace sphinxcontrib/tikz.py \
+      --replace "config.latex_engine" "'${texLive}/bin/pdflatex'" \
+      --replace "system(['pdf2svg'" "system(['${pdf2svg}/bin/pdf2svg'"
+  '';
+
+  propagatedBuildInputs = [ sphinx ];
+
+  # no tests in package
+  doCheck = false;
+
+  pythonImportsCheck = [ "sphinxcontrib.tikz" ];
+
+  meta = with lib; {
+    description = "TikZ extension for Sphinx";
+    homepage = "https://bitbucket.org/philexander/tikz";
+    maintainers = with maintainers; [ costrouc ];
+    license = licenses.bsd3;
+  };
+
+}