lineageos: restrict updater to devices we can support

[Atemu]

The updater breaks all the time because of inconsistent repo setups/naming for devices. There's also, like, a ton of them which makes updating the device dirs an extremely slow process.

Let's restrict the devices we support to the set of devices that anyone of us actually has and can verify builds on. People can simply submit new devices via PR to the JSON or whatever that defines which devices are available.

To do this, the updater must be changed to only fetch device dirs for these few device codenames.