[components][usb] fix compile warning in cdc_vcom.c
@@ -738,7 +738,7 @@ static rt_size_t _vcom_rb_block_put(struct vcom *data, const rt_uint8_t *buf, rt
return size;
}
-static rt_size_t _vcom_tx(struct rt_serial_device *serial, rt_uint8_t *buf, rt_size_t size,rt_uint32_t direction)
+static rt_size_t _vcom_tx(struct rt_serial_device *serial, rt_uint8_t *buf, rt_size_t size, int direction)
{
struct ufunction *func;
struct vcom *data;
