message: Avoid generating a params variable when there are no params to extract
diff: @@ -272,10 +272,12 @@ void GenerateImportForOp(FILE* fp, const std::string& op_name,
  }
  fprintf(fp, " case BuiltinOperator_%s: {\n", op_name.c_str());
  + if (options->num_elems != 0) {
  fprintf(fp,
  " const auto* params = reinterpret_cast<const "
  "%s*>(builtin_op_data);\n",
  struct_name.c_str());
  + }
  for (size_t i = 0; i < options->num_elems; i++) {
  std::string elem_name = options->names[i];
  