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/opam-core/default.nix

@@ -0,0 +1,22 @@
+{ lib, buildDunePackage, unzip
+, opam, ocamlgraph, re, cppo }:
+
+buildDunePackage rec {
+  pname = "opam-core";
+
+  inherit (opam) src version;
+
+  useDune2 = true;
+
+  nativeBuildInputs = [ unzip cppo ];
+  propagatedBuildInputs = [ ocamlgraph re ];
+
+  # get rid of check for curl at configure time
+  # opam-core does not call curl at run time
+  configureFlags = [ "--disable-checks" ];
+
+  meta = opam.meta // {
+    description = "Small standard library extensions, and generic system interaction modules used by opam";
+    maintainers = with lib.maintainers; [ sternenseemann ];
+  };
+}