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/potr/default.nix

@@ -0,0 +1,20 @@
+{ lib, fetchPypi, buildPythonPackage, pycrypto }:
+
+buildPythonPackage rec {
+  pname = "python-potr";
+  version = "1.0.2";
+
+  src = fetchPypi {
+    inherit pname version;
+    sha256 = "f95b9a7feaf8e3a6aaa898609f8a2ada55518cf52fc09152775c4c59c99b8ea6";
+  };
+
+  propagatedBuildInputs = [ pycrypto ];
+
+  meta = with lib; {
+    description = "A pure Python OTR implementation";
+    homepage = "http://python-otr.pentabarf.de/";
+    license = licenses.lgpl3Plus;
+    maintainers = with maintainers; [ ];
+  };
+}