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/tools/security/rnp/default.nix

@@ -0,0 +1,56 @@
+{ lib
+, stdenv
+, asciidoctor
+, botan2
+, bzip2
+, cmake
+, fetchFromGitHub
+, gnupg
+, gtest
+, json_c
+, pkg-config
+, python3
+, zlib
+}:
+
+stdenv.mkDerivation rec {
+  pname = "rnp";
+  version = "0.16.0";
+
+  src = fetchFromGitHub {
+    owner = "rnpgp";
+    repo = "rnp";
+    rev = "v${version}";
+    sha256 = "u0etVslTBF9fBqnpVBofYsm0uC/eR6gO3lhwzqua5Qw=";
+  };
+
+  buildInputs = [ zlib bzip2 json_c botan2 ];
+
+  cmakeFlags = [
+    "-DCMAKE_INSTALL_PREFIX=${placeholder "out"}"
+    "-DBUILD_SHARED_LIBS=on"
+    "-DBUILD_TESTING=on"
+    "-DDOWNLOAD_GTEST=off"
+    "-DDOWNLOAD_RUBYRNP=off"
+  ];
+
+  nativeBuildInputs = [ asciidoctor cmake gnupg gtest pkg-config python3 ];
+
+  # NOTE: check-only inputs should ideally be moved to checkInputs, but it
+  # would fail during buildPhase.
+  # checkInputs = [ gtest python3 ];
+
+  outputs = [ "out" "lib" "dev" ];
+
+  preConfigure = ''
+    echo "v${version}" > version.txt
+  '';
+
+  meta = with lib; {
+    homepage = "https://github.com/rnpgp/rnp";
+    description = "High performance C++ OpenPGP library, fully compliant to RFC 4880";
+    license = licenses.bsd2;
+    platforms = platforms.all;
+    maintainers = with maintainers; [ ribose-jeffreylau ];
+  };
+}