Merge pull request #3516 from yangjie11/yj_dev

[components][serial]关闭uart时，反初始化tx_dma->data_queue，防止内存泄漏

components/drivers/serial/serial.c

@@ -785,6 +785,8 @@ static rt_err_t rt_serial_close(struct rt_device *dev)
         tx_dma = (struct rt_serial_tx_dma*)serial->serial_tx;
         RT_ASSERT(tx_dma != RT_NULL);
 
+        rt_data_queue_deinit(&(tx_dma->data_queue));
+
         rt_free(tx_dma);
         serial->serial_tx = RT_NULL;
         dev->open_flag &= ~RT_DEVICE_FLAG_DMA_TX;