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/xattr/default.nix

@@ -0,0 +1,32 @@
+{ lib
+, buildPythonPackage
+, fetchPypi
+, python
+, cffi
+}:
+
+buildPythonPackage rec {
+  pname = "xattr";
+  version = "0.9.9";
+
+  src = fetchPypi {
+    inherit pname version;
+    sha256 = "09cb7e1efb3aa1b4991d6be4eb25b73dc518b4fe894f0915f5b0dcede972f346";
+  };
+
+  propagatedBuildInputs = [ cffi ];
+
+  # https://github.com/xattr/xattr/issues/43
+  doCheck = false;
+
+  postBuild = ''
+    ${python.interpreter} -m compileall -f xattr
+  '';
+
+  meta = with lib; {
+    homepage = "https://github.com/xattr/xattr";
+    description = "Python wrapper for extended filesystem attributes";
+    license = licenses.mit;
+  };
+
+}