ocamlPackages.eliom: no dependency on ocamlnet

pkgs/development/ocaml-modules/eliom/default.nix

···
 , js_of_ocaml-lwt
 , js_of_ocaml-tyxml
 , lwt_ppx
-, ocamlnet
 , ocsipersist
 }:
 
···
   buildInputs = [
     js_of_ocaml-ocamlbuild
     js_of_ocaml-ppx_deriving_json
-    ocamlnet
     ppx_optcomp
   ];