add class driver deinit

src/class/cdc/cdc_device.h

@@ -247,6 +247,7 @@ static inline bool tud_cdc_write_clear(void)
 // INTERNAL USBD-CLASS DRIVER API
 //--------------------------------------------------------------------+
 void     cdcd_init            (void);
+bool     cdcd_deinit          (void);
 void     cdcd_reset           (uint8_t rhport);
 uint16_t cdcd_open            (uint8_t rhport, tusb_desc_interface_t const * itf_desc, uint16_t max_len);
 bool     cdcd_control_xfer_cb (uint8_t rhport, uint8_t stage, tusb_control_request_t const * request);