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/ocaml/cppo/ocamlbuild.nix

@@ -0,0 +1,17 @@
+{ lib, buildDunePackage, cppo, ocamlbuild }:
+
+if lib.versionOlder (lib.getVersion cppo) "1.6"
+then cppo
+else
+
+buildDunePackage rec {
+  pname = "cppo_ocamlbuild";
+
+  inherit (cppo) version useDune2 src;
+
+  propagatedBuildInputs = [ ocamlbuild ];
+
+  meta = cppo.meta // {
+    description = "Plugin to use cppo with ocamlbuild";
+  };
+}