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/cstruct/sexp.nix

@@ -0,0 +1,18 @@
+{ lib, buildDunePackage, ocaml, alcotest, cstruct, sexplib }:
+
+if lib.versionOlder (cstruct.version or "1") "3"
+then cstruct
+else
+
+buildDunePackage rec {
+  pname = "cstruct-sexp";
+  inherit (cstruct) version src useDune2 meta;
+
+  minimumOCamlVersion = "4.03";
+
+  # alcotest is only available on OCaml >= 4.05 due to fmt
+  doCheck = lib.versionAtLeast ocaml.version "4.05";
+  checkInputs = [ alcotest ];
+
+  propagatedBuildInputs = [ cstruct sexplib ];
+}