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/ocaml-modules/expat/default.nix

@@ -0,0 +1,35 @@
+{ stdenv, lib, fetchFromGitHub, expat, ocaml, findlib, ounit }:
+
+stdenv.mkDerivation rec {
+  pname = "ocaml${ocaml.version}-expat";
+  version = "1.1.0";
+
+  src = fetchFromGitHub {
+    owner = "whitequark";
+    repo = "ocaml-expat";
+    rev = "v${version}";
+    sha256 = "07wm9663z744ya6z2lhiz5hbmc76kkipg04j9vw9dqpd1y1f2x3q";
+  };
+
+  prePatch = ''
+    substituteInPlace Makefile --replace "gcc" "\$(CC)"
+  '';
+
+  nativeBuildInputs = [ ocaml findlib ];
+  buildInputs = [ expat ounit ];
+
+  strictDeps = true;
+
+  doCheck = lib.versionOlder ocaml.version "4.06";
+  checkTarget = "testall";
+
+  createFindlibDestdir = true;
+
+  meta = {
+    description = "OCaml wrapper for the Expat XML parsing library";
+    license = lib.licenses.mit;
+    maintainers = [ lib.maintainers.vbgl ];
+    inherit (src.meta) homepage;
+    inherit (ocaml.meta) platforms;
+  };
+}