update the polling interval to be used next iteration

def _poll_update_interval(self):
        """ update the polling interval to be used next iteration """
        # Increase by 1 second every 3 polls
        if old_div(self.poll_count, 3) > self.poll_interval_level:
            self.poll_interval_level += 1
            self.poll_interval_s += 1
            self.logger.info(
                "Increased polling interval to %d seconds", self.poll_interval_s
            )