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/grpcio/default.nix

@@ -0,0 +1,46 @@
+{ lib, stdenv
+, buildPythonPackage
+, grpc
+, six
+, protobuf
+, enum34 ? null
+, futures ? null
+, isPy27
+, pkg-config
+, cython
+, c-ares
+, openssl
+, zlib
+}:
+
+buildPythonPackage rec {
+  inherit (grpc) src version;
+  pname = "grpcio";
+
+  outputs = [ "out" "dev" ];
+
+  nativeBuildInputs = [ cython pkg-config ];
+
+  buildInputs = [ c-ares openssl zlib ];
+  propagatedBuildInputs = [ six protobuf ]
+    ++ lib.optionals (isPy27) [ enum34 futures ];
+
+  preBuild = lib.optionalString stdenv.isDarwin "unset AR";
+
+  GRPC_BUILD_WITH_BORING_SSL_ASM = "";
+  GRPC_PYTHON_BUILD_SYSTEM_OPENSSL = 1;
+  GRPC_PYTHON_BUILD_SYSTEM_ZLIB = 1;
+  GRPC_PYTHON_BUILD_SYSTEM_CARES = 1;
+
+  # does not contain any tests
+  doCheck = false;
+
+  pythonImportsCheck = [ "grpc" ];
+
+  meta = with lib; {
+    description = "HTTP/2-based RPC framework";
+    license = licenses.asl20;
+    homepage = "https://grpc.io/grpc/python/";
+    maintainers = with maintainers; [ SuperSandro2000 ];
+  };
+}