Nvidia akmods logic needs to be updated

[fiftydinar]

Ublue dropped versioning, so it always builds the newest one.
Which means that nvidia-version entry is no longer needed.

Maybe nvidia: false by default can substitute legacy nvidia-version entry.

They also build the image in proprietary & open kernel module, so they are versioned like this:
ghcr.io/ublue-os/akmods-nvidia:main-${OS_VERSION}
ghcr.io/ublue-os/akmods-nvidia-open:main-${OS_VERSION}

Maybe nvidia: open/proprietary entry option looks good.

What do you think?

[gmpinder]

I don't know if switching from a boolean to an enum would be a smart move. If I can find a way to accept both a bool and enum, that could work. We would have nvidia: true be equivalent to nvidia: proprietary since that logic would bear the same image. For nvidia-version, we can just ignore it/let the json schema handle validation.