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/networking/ratools/default.nix

@@ -0,0 +1,28 @@
+{ lib, stdenv, fetchFromGitHub }:
+
+stdenv.mkDerivation rec {
+  pname = "ratools";
+  version = "0.6.2";
+
+  src = fetchFromGitHub {
+    owner = "danrl";
+    repo = "ratools";
+    rev = "v${version}";
+    sha256 = "07m45bn9lzgbfihmxic23wqp73nxg5ihrvkigr450jq6gzvgwawq";
+  };
+
+  makeFlags = [ "-C" "src" ];
+
+  installPhase = ''
+    install -vD bin/* -t $out/bin
+    install -vD man/* -t $out/share/man/man8
+  '';
+
+  meta = with lib; {
+    description = "A fast, dynamic, multi-threading framework for IPv6 Router Advertisements";
+    homepage = "https://github.com/danrl/ratools";
+    license = licenses.asl20;
+    platforms = platforms.linux;
+    maintainers = [ maintainers.fpletz ];
+  };
+}