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/backcall/default.nix

@@ -0,0 +1,28 @@
+{ lib
+, buildPythonPackage
+, fetchPypi
+, pytest
+}:
+
+buildPythonPackage rec {
+  pname = "backcall";
+  version = "0.2.0";
+
+  src = fetchPypi {
+    inherit pname version;
+    sha256 = "5cbdbf27be5e7cfadb448baf0aa95508f91f2bbc6c6437cd9cd06e2a4c215e1e";
+  };
+
+  checkInputs = [ pytest ];
+
+  checkPhase = ''
+    py.test
+  '';
+
+  meta = {
+    description = "Specifications for callback functions passed in to an API";
+    homepage = "https://github.com/takluyver/backcall";
+    license = lib.licenses.bsd3;
+  };
+
+}