cbcd1d6a

By: Tom Sydney Kerckhove <syd@cs-syd.eu>

accept falcon-sensor .deb as a flake input

Instead of requiring the .deb to be checked into the repo, accept it
as a flake input that can be overridden at build time:

  nix build .#falcon-sensor --override-input falcon-sensor-deb path:/tmp/falcon-sensor.deb

Also make the CID optional so the module can be used in AMI builds
where the CID is configured at runtime.