refine VPNProfile.ensureCreateEnforcementEnv for different platforms
refine VPNProfile.ensureCreateEnforcementEnv for different platforms

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