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/pycflow2dot/default.nix

@@ -0,0 +1,41 @@
+{ lib
+, buildPythonPackage
+, fetchPypi
+, cflow
+, graphviz
+, pydot
+, networkx
+, which
+}:
+
+buildPythonPackage rec {
+  pname = "pycflow2dot";
+  version = "0.2.3";
+
+  src = fetchPypi {
+    inherit pname version;
+    sha256 = "1zm8x2pd0q6zza0fw7hg9g1qvybfnjq6ql9b8mh2fc45l7l25655";
+  };
+
+  propagatedBuildInputs = [
+    cflow
+    graphviz
+    pydot
+    networkx
+    which
+  ];
+
+  pythonImportsCheck = [ "pycflow2dot" ];
+  checkPhase = ''
+    cd tests
+    export PATH=$out/bin:$PATH
+    make all
+  '';
+
+  meta = with lib; {
+    description = "Layout C call graphs from cflow using GraphViz dot";
+    homepage    = "https://github.com/johnyf/pycflow2dot";
+    license     = licenses.gpl3Plus;
+    maintainers = with maintainers; [ evils ];
+  };
+}