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/letsencrypt/default.nix

@@ -0,0 +1,63 @@
+{ buildDunePackage
+, lib
+, fetchurl
+, asn1-combinators
+, uri
+, base64
+, logs
+, fmt
+, lwt
+, mirage-crypto
+, mirage-crypto-ec
+, mirage-crypto-pk
+, mirage-crypto-rng
+, x509
+, yojson
+, ounit
+, ptime
+, domain-name
+, cstruct
+}:
+
+buildDunePackage rec {
+  pname = "letsencrypt";
+  version = "0.4.1";
+
+  src = fetchurl {
+    url = "https://github.com/mmaker/ocaml-letsencrypt/releases/download/v${version}/letsencrypt-v${version}.tbz";
+    sha256 = "f90875f5c9bdcab4c8be5ec7ebe9ea763030fa708e02857300996bb16e7c2070";
+  };
+
+  minimumOCamlVersion = "4.08";
+  useDune2 = true;
+
+  buildInputs = [
+    fmt
+    ptime
+    domain-name
+  ];
+
+  propagatedBuildInputs = [
+    logs
+    yojson
+    lwt
+    base64
+    mirage-crypto
+    mirage-crypto-ec
+    mirage-crypto-pk
+    asn1-combinators
+    x509
+    uri
+    cstruct
+  ];
+
+  doCheck = true;
+  checkInputs = [ ounit ];
+
+  meta = {
+    description = "ACME implementation in OCaml";
+    license = lib.licenses.bsd2;
+    maintainers = [ lib.maintainers.sternenseemann ];
+    homepage = "https://github.com/mmaker/ocaml-letsencrypt";
+  };
+}