fldigi: 4.0.16 -> 4.0.17

Semi-automatic update generated by https://github.com/ryantm/nixpkgs-update tools.

This update was made based on information from https://repology.org/metapackage/fldigi/versions.

These checks were done:

- built on NixOS
- /nix/store/87mml563vxqamznb9i9kfyi1pz9ldkxj-fldigi-4.0.17/bin/fldigi passed the binary check.
- Warning: no invocation of /nix/store/87mml563vxqamznb9i9kfyi1pz9ldkxj-fldigi-4.0.17/bin/flarq had a zero exit code or showed the expected version
- 1 of 2 passed binary check by having a zero exit code.
- 0 of 2 passed binary check by having the new version present in output.
- found 4.0.17 with grep in /nix/store/87mml563vxqamznb9i9kfyi1pz9ldkxj-fldigi-4.0.17
- directory tree listing: https://gist.github.com/fa90913d77a29b869e48c2c455710bd7
- du listing: https://gist.github.com/9172dd2cacb00accaffafe285aacea29