use MANAGED_BY_FIREROUTER instead of uname -m in flush_iptables.sh
use MANAGED_BY_FIREROUTER instead of uname -m in flush_iptables.sh

(cherry picked from commit 1a849709f94a20174b102e8e4ad5d2d1c54df267)

MelvinTo/firewalla,firewalla/firewalla,MelvinTo/firewalla,MelvinTo/firewalla,firewalla/firewalla,MelvinTo/firewalla,firewalla/firewalla,firewalla/firewalla,MelvinTo/firewalla,firewalla/firewalla