clean compiler warning.

class/hub/usbd_hub.c

@@ -103,4 +103,4 @@ void usbd_hub_add_interface(usbd_class_t *devclass, usbd_interface_t *intf)
     intf->vendor_handler = NULL;
     intf->notify_handler = hub_notify_handler;
     usbd_class_add_interface(devclass, intf);
-}
+}

class/hub/usbh_hub.c

@@ -516,4 +516,4 @@ CLASS_INFO_DEFINE const struct usbh_class_info hub_class_info = {
     .vid = 0x00,
     .pid = 0x00,
     .class_driver = &hub_class_driver
-};
+};