fix(xcp_service.configure): do not fail on --help

Fixes: 1d42c05 ("test(xapi_globs): add a unit test that xapi globs parsing works")

Signed-off-by: Edwin Török <[email protected]>

ocaml/xapi-idl/lib/xcp_service.ml

@@ -464,7 +464,10 @@ let configure ?(argv = Sys.argv) ?(options = []) ?(resources = []) () =
           (fun _ -> failwith "Invalid argument")
           (Printf.sprintf "Usage: %s [-config filename]" Sys.argv.(0))
     )
-  with Failure msg -> prerr_endline msg ; flush stderr ; exit 1
+  with
+  | Failure msg -> prerr_endline msg ; flush stderr ; exit 1
+  | Arg.Bad msg -> Printf.eprintf "%s" msg; exit 2
+  | Arg.Help msg -> Printf.printf "%s" msg; exit 0
 
 let configure2 ~name ~version ~doc ?(options = []) ?(resources = []) () =
   configure_common ~options ~resources @@ fun config_spec ->