message: fix function declare
diff: @@ -37,19 +37,19 @@ static size_t dns_cache_capacity = 1000;
  static time_t dns_cache_expire = 60;
  static LRUCache *dns_cache = nullptr;
  -void set_dns_cache_expire(time_t expire)
  +void swoole::set_dns_cache_expire(time_t expire)
  {
  dns_cache_expire = expire;
  }
  -void set_dns_cache_capacity(size_t capacity)
  +void swoole::set_dns_cache_capacity(size_t capacity)
  {
  dns_cache_capacity = capacity;
  delete dns_cache;
  dns_cache = nullptr;
  }
  -void clear_dns_cache()
  +void swoole::clear_dns_cache()
  {
  dns_cache->clear();
  }
  