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/tools/misc/objconv/default.nix

@@ -0,0 +1,39 @@
+{ lib, stdenv, fetchurl, unzip }:
+
+stdenv.mkDerivation rec {
+  pname = "objconv";
+  version = "2.52";
+
+  src = fetchurl {
+    # Versioned archive of objconv sources maintained by orivej.
+    url = "https://archive.org/download/objconv/${pname}-${version}.zip";
+    sha256 = "0r117r7yvqvvdgwgwxpkyzi6p5nm0xb6p67wvkmvggm9fdyl3z8v";
+  };
+
+  nativeBuildInputs = [ unzip ];
+
+  outputs = [ "out" "doc" ];
+
+  unpackPhase = ''
+    mkdir -p "$name"
+    cd "$name"
+    unpackFile "$src"
+    unpackFile source.zip
+  '';
+
+  buildPhase = "c++ -o objconv -O2 *.cpp";
+
+  installPhase = ''
+    mkdir -p $out/bin $out/doc/objconv
+    mv objconv $out/bin
+    mv objconv-instructions.pdf $out/doc/objconv
+  '';
+
+  meta = with lib; {
+    description = "Object and executable file converter, modifier and disassembler";
+    homepage = "https://www.agner.org/optimize/";
+    license = licenses.gpl2;
+    maintainers = with maintainers; [ orivej vrthra ];
+    platforms = platforms.unix;
+  };
+}