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/build-support/ocaml/default.nix

@@ -0,0 +1,36 @@
+{ lib, stdenv, writeText, ocaml, findlib, ocamlbuild, camlp4 }:
+
+{ pname ? args.name, version, nativeBuildInputs ? [],
+  createFindlibDestdir ?  true,
+  dontStrip ? true,
+  minimumSupportedOcamlVersion ? null,
+  hasSharedObjects ? false,
+  setupHook ? null,
+  meta ? {}, ...
+}@args:
+let
+  defaultMeta = {
+    platforms = ocaml.meta.platforms or [];
+  };
+in
+  assert minimumSupportedOcamlVersion != null ->
+          lib.versionOlder minimumSupportedOcamlVersion ocaml.version;
+
+stdenv.mkDerivation (args // {
+  name = "ocaml-${pname}-${version}";
+
+  nativeBuildInputs = [ ocaml findlib ocamlbuild camlp4 ] ++ nativeBuildInputs;
+
+  strictDeps = true;
+
+  setupHook = if setupHook == null && hasSharedObjects
+  then writeText "setupHook.sh" ''
+    export CAML_LD_LIBRARY_PATH="''${CAML_LD_LIBRARY_PATH-}''${CAML_LD_LIBRARY_PATH:+:}''$1/lib/ocaml/${ocaml.version}/site-lib/${pname}/"
+    ''
+  else setupHook;
+
+  inherit createFindlibDestdir;
+  inherit dontStrip;
+
+  meta = defaultMeta // meta;
+})