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/secp256k1/default.nix

@@ -0,0 +1,46 @@
+{ lib
+, buildPythonPackage
+, fetchPypi
+, pkg-config
+, pytestCheckHook
+, cffi
+, secp256k1
+}:
+
+buildPythonPackage rec {
+  pname = "secp256k1";
+  version = "0.14.0";
+
+  src = fetchPypi {
+    inherit pname version;
+    sha256 = "82c06712d69ef945220c8b53c1a0d424c2ff6a1f64aee609030df79ad8383397";
+  };
+
+  postPatch = ''
+    # don't do hacky tarball download + setuptools check
+    sed -i '38,54d' setup.py
+    substituteInPlace setup.py --replace ", 'pytest-runner==2.6.2'" ""
+  '';
+
+  nativeBuildInputs = [ pkg-config ];
+
+  propagatedBuildInputs = [ cffi secp256k1 ];
+
+  checkInputs = [ pytestCheckHook ];
+
+  # Tests are not included in archive
+  doCheck = false;
+
+  preConfigure = ''
+    cp -r ${secp256k1.src} libsecp256k1
+    export INCLUDE_DIR=${secp256k1}/include
+    export LIB_DIR=${secp256k1}/lib
+  '';
+
+  meta = {
+    homepage = "https://github.com/ludbb/secp256k1-py";
+    description = "Python FFI bindings for secp256k1";
+    license = with lib.licenses; [ mit ];
+    maintainers = with lib.maintainers; [ ];
+  };
+}