Push state to QSUSB, retry with backoff.

async def async_set_qs_value(self, qsid, val, success_cb=None):
        """Push state to QSUSB, retry with backoff."""
        set_url = URL_SET.format(self._url, qsid, val)
        for _repeat in range(1, 6):
            set_result = await self.get_json(set_url, 2)
            if set_result and set_result.get('data', 'NO REPLY') != 'NO REPLY':
                if success_cb:
                    success_cb()
                return True
            await asyncio.sleep(0.01 * _repeat)
        _LOGGER.error("Unable to set %s", set_url)
        return False