TYT MD-380 screen flip

HX8353_MD3x0.cpp

for(uint8_t y = startRow; y < endRow; y++)
{
  for(uint8_t x = 0; x < SCREEN_WIDTH; x++)
  {
    if(y<SCREEN_HEIGHT/2)
    {
      size_t pos1 = x + y * SCREEN_WIDTH;
      size_t pos2 = x + (SCREEN_HEIGHT-1-y) * SCREEN_WIDTH;
      uint16_t tmp = frameBuffer[pos1];
      frameBuffer[pos1] = __builtin_bswap16(frameBuffer[pos2]);
      frameBuffer[pos2] = tmp;
    }
    else
    {
      size_t pos = x + y * SCREEN_WIDTH;
      frameBuffer[pos] = __builtin_bswap16(frameBuffer[pos]);
    }
  }
}