Firewall rules

[Revival8697]

Handheld doesn't get a firewall by default. We should set up some gaming related rules as a step toward enabling the firewall OoTB in the future.

• Steam:
  • https://help.steampowered.com/en/faqs/view/2EA8-4D75-DA21-31EB
  • https://help.steampowered.com/en/faqs/view/46BD-6BA8-B012-CE43
• Sunshine + Moonlight: https://github.com/moonlight-stream/moonlight-docs/wiki/Setup-Guide#manual-port-forwarding-advanced