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/irmin/fs.nix

@@ -0,0 +1,23 @@
+{ lib, buildDunePackage, irmin, irmin-test }:
+
+buildDunePackage rec {
+
+  pname = "irmin-fs";
+
+  inherit (irmin) version src;
+
+  propagatedBuildInputs = [ irmin ];
+
+  useDune2 = true;
+
+  checkInputs = lib.optional doCheck irmin-test;
+
+  doCheck = true;
+
+  meta = irmin.meta // {
+    description = "Generic file-system backend for Irmin";
+  };
+
+}
+
+