add class driver deinit

src/class/dfu/dfu_rt_device.h

@@ -43,6 +43,7 @@ void tud_dfu_runtime_reboot_to_dfu_cb(void);
 // Internal Class Driver API
 //--------------------------------------------------------------------+
 void     dfu_rtd_init(void);
+bool     dfu_rtd_deinit(void);
 void     dfu_rtd_reset(uint8_t rhport);
 uint16_t dfu_rtd_open(uint8_t rhport, tusb_desc_interface_t const * itf_desc, uint16_t max_len);
 bool     dfu_rtd_control_xfer_cb(uint8_t rhport, uint8_t stage, tusb_control_request_t const * request);