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/games/gmad/default.nix

@@ -0,0 +1,35 @@
+{ lib, stdenv, fetchFromGitHub, premake4, bootil }:
+
+stdenv.mkDerivation rec {
+  pname = "gmad";
+  version = "unstable-2020-02-24";
+
+  meta = {
+    description = "Garry's Mod Addon Creator and Extractor";
+    homepage = "https://github.com/Facepunch/gmad";
+    license = lib.licenses.unfree;
+    maintainers = [ lib.maintainers.abigailbuccaneer ];
+    platforms = lib.platforms.all;
+  };
+
+  src = fetchFromGitHub {
+    owner = "Facepunch";
+    repo = "gmad";
+    rev = "5236973a2fcbb3043bdd3d4529ce68b6d938ad93";
+    sha256="04an17nvnj38mpi0w005v41ib8ynb5qhgrdkmsda4hq7l1gn276s";
+  };
+
+  buildInputs = [ premake4 bootil ];
+
+  targetName =
+    if stdenv.isLinux then "gmad_linux"
+    else if stdenv.isDarwin then "gmad_osx"
+    else "gmad";
+
+  premakeFlags = [ "--bootil_lib=${bootil}/lib" "--bootil_inc=${bootil}/include" ];
+
+  installPhase = ''
+    mkdir -p $out/bin
+    cp ${targetName} $out/bin/gmad
+  '';
+}