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/chacha/default.nix

@@ -0,0 +1,41 @@
+{ lib
+, buildDunePackage
+, fetchurl
+, ocaml
+
+, alcotest
+, cstruct
+, mirage-crypto
+}:
+
+buildDunePackage rec {
+  pname = "chacha";
+  version = "1.0.0";
+
+  src = fetchurl {
+    url = "https://github.com/abeaumont/ocaml-chacha/releases/download/${version}/${pname}-${version}.tbz";
+    sha256 = "sha256-t8dOMQQDpje0QbuOhjSIa3xnXuXcxMVTLENa/rwdgA4=";
+  };
+
+  useDune2 = true;
+
+  minimumOCamlVersion = "4.02";
+
+  propagatedBuildInputs = [ cstruct mirage-crypto ];
+
+  # alcotest isn't available for OCaml < 4.05 due to fmt
+  doCheck = lib.versionAtLeast ocaml.version "4.05";
+  checkInputs = [ alcotest ];
+
+  meta = {
+    homepage = "https://github.com/abeaumont/ocaml-chacha";
+    description = "ChaCha20, ChaCha12 and ChaCha8 encryption functions, in OCaml";
+    longDescription = ''
+      An OCaml implementation of ChaCha functions, both ChaCha20 and the reduced
+      ChaCha8 and ChaCha12 functions. The hot loop is implemented in C for efficiency
+      reasons.
+    '';
+    license = lib.licenses.bsd2;
+    maintainers = with lib.maintainers; [ fufexan ];
+  };
+}