Merge "Prevent infinite loop on zero length USB descriptors" am: a40c30d1...

    if (iter->curr_desc >= iter->config_end)

        return NULL;

    next = (struct usb_descriptor_header*)iter->curr_desc;

    // Corrupt descriptor with zero length, cannot continue iterating

    if (next->bLength == 0) {

       D("usb_descriptor_iter_next got zero length USB descriptor, ending iteration\n");

       return NULL;

    }

    iter->curr_desc += next->bLength;

    return next;

}