discover.ml: eliminate the caml_file global
discover.ml: eliminate the caml_file global

ocamllabs/ocaml-ctypes,yallop/ocaml-ctypes,ocamllabs/ocaml-ctypes,sjfloat/ocaml-ctypes,dsheets/ocaml-ctypes,whitequark/ocaml-ctypes,sjfloat/ocaml-ctypes,sjfloat/ocaml-ctypes,dsheets/ocaml-ctypes,whitequark/ocaml-ctypes,dsheets/ocaml-ctypes,yallop/ocaml-ctypes,whitequark/ocaml-ctypes