枚举

异步任务完成状态定义：

enum HixlCompleteStatus {
  HIXL_COMPLETE_STATUS_WAITING,
  HIXL_COMPLETE_STATUS_COMPLETED,
  HIXL_COMPLETE_STATUS_TIMEOUT,
  HIXL_COMPLETE_STATUS_FAILED
};

说明：HIXL_COMPLETE_STATUS_TIMEOUT和HIXL_COMPLETE_STATUS_FAILED当前为预留字段。