Don't crash on driver without init()

Handle init() like deinit()

Author: ceedriic

src/host/usbh.c

@@ -544,7 +544,7 @@ bool tuh_rhport_init(uint8_t rhport, const tusb_rhport_init_t* rh_init) {
     // Class drivers
     for (uint8_t drv_id = 0; drv_id < TOTAL_DRIVER_COUNT; drv_id++) {
       usbh_class_driver_t const* driver = get_driver(drv_id);
-      if (driver != NULL) {
+      if (driver != NULL && driver->init) {
         TU_LOG_USBH("%s init\r\n", driver->name);
         driver->init();
       }