message: Use swSocket_set_buffer_size.
diff: @@ -1520,8 +1520,7 @@ int swServer_add_systemd_socket(swServer *serv)
  //dgram socket, setting socket buffer size
  if (swSocket_is_dgram(ls->type))
  {
  - setsockopt(sock, SOL_SOCKET, SO_SNDBUF, &ls->socket_buffer_size, sizeof(int));
  - setsockopt(sock, SOL_SOCKET, SO_RCVBUF, &ls->socket_buffer_size, sizeof(int));
  + swSocket_set_buffer_size(sock, ls->socket_buffer_size);
  }
  //O_NONBLOCK & O_CLOEXEC
  swoole_fcntl_set_option(sock, 1, 1);
  @@ -1617,8 +1616,7 @@ swListenPort* swServer_add_port(swServer *serv, int type, const char *host, int
  //dgram socket, setting socket buffer size
  if (swSocket_is_dgram(ls->type))
  {
  - setsockopt(sock, SOL_SOCKET, SO_SNDBUF, &ls->socket_buffer_size, sizeof(int));
  - setsockopt(sock, SOL_SOCKET, SO_RCVBUF, &ls->socket_buffer_size, sizeof(int));
  + swSocket_set_buffer_size(sock, ls->socket_buffer_size);
  }
  //O_NONBLOCK & O_CLOEXEC
  swoole_fcntl_set_option(sock, 1, 1);
  