Device / firmware package changes for SDM845 sensor support

This is !4050 (merged), but without the iio-sensor-proxy changes. I decided to submit this after talking to @dylanvanassche, my summary of that conversation + my interpretation of it is below. Feel free to dispute any part of this 😅

Why merge this separately, and now?

Rebasing !4050 (merged) probably sucks (cc @pabloyoyoista), and there's an open regression preventing that MR from being merged. That regression depends on an upgrade to iio-sensor-proxy. If we avoid upgrading that package (i.e. this branch), then there seem to be a low risk of causing regressions, and it would let us pretty much avoid all rebasing pain when rebasing onto pmaports.

Some feedback in !4050 (merged) was to match on device tree compatible in the udev rule, I've heard that this would simplify this patch considerably. I don't believe it's necessary to block on this feedback though, it could be added at a later time and we could open an issue to keep track it.

Why not just merge !4050 (merged) now?

It causes a regression on at least one device (OP6T/fajita) tested in that MR. There were problems with the expected display rotation direction.

The benefit of having these sensors working on these platforms is (IMHO) huge, I've been using an OP6 with !4050 (merged) for a few days now and it has been a lot more fun to use than before 😁