Support for v4.4 legacy versions

[StarGate01]

I am currently working on the migration of a rather large IDF project from 4.4 to 5.x . While this repo works great for 5.x, 4.4 does not work due to the changed tool lists and the incompatible python dependencies.

I can fix up all of this myself in a fork, but I would like to discuss how this could be integrated into this repo, such that both the last 4.4 version as well as the actual up-to-date 5.x versions are supported.

[mirrexagon]

If the only changes required to the Nix code between ESP-IDF v5 and v4 are the ESP-IDF source revision and the Python package versions (assuming that the versions of packages already in nixpkgs work fine and just the ESP-IDF-specific packages need different versions), then I imagine we can add a python-packages parameter to the ESP-IDF derivation and instantiate one for v5 and one for v4.

Do you know if other changes to the Nix code are required?