Remove no more needed code.

main.ml

@@ -43,8 +43,7 @@ let setup_logs =
 
 (* Commands. *)
 
-let verify cmd model property solver solver_raw_options () =
-  ignore solver_raw_options;
+let verify cmd model property solver raw_options () =
   Logs.debug
     (fun m ->
        m "Command `%s' with@ model `%s',@ property `%s' and@ solver `%s'."
@@ -53,7 +52,7 @@ let verify cmd model property solver solver_raw_options () =
     let open Result in
     Model.build ~filename:model >>= fun model ->
     Property.build ~filename:property >>= fun property ->
-    Solver.exec ?raw_options:solver_raw_options solver property model
+    Solver.exec ?raw_options solver property model
   in
   match do_verify () with
   | Ok () -> Logs.app (fun m -> m "Done.")

solver.ml

@@ -146,7 +146,6 @@ let build_command ?raw_options solver property model =
   end
 
 let exec ?raw_options solver property model =
-  ignore raw_options;
   let open Result in
   (* Check solver availability in PATH. *)
   check_availability solver >>= fun () ->