pkg/lvgl: only swap byte when ili9341 is used
pkg/lvgl: only swap byte when ili9341 is used

kaspar030/RIOT,miri64/RIOT,jasonatran/RIOT,kYc0o/RIOT,OlegHahm/RIOT,RIOT-OS/RIOT,jasonatran/RIOT,RIOT-OS/RIOT,kYc0o/RIOT,RIOT-OS/RIOT,kYc0o/RIOT,miri64/RIOT,ant9000/RIOT,ant9000/RIOT,kaspar030/RIOT,miri64/RIOT,kaspar030/RIOT,kYc0o/RIOT,ant9000/RIOT,miri64/RIOT,jasonatran/RIOT,miri64/RIOT,OlegHahm/RIOT,OlegHahm/RIOT,kaspar030/RIOT,ant9000/RIOT,jasonatran/RIOT,ant9000/RIOT,RIOT-OS/RIOT,OlegHahm/RIOT,RIOT-OS/RIOT,jasonatran/RIOT,kaspar030/RIOT,kYc0o/RIOT,OlegHahm/RIOT