Brightness keys on Legion 5 laptop are changing brightness level on wrong GPU

[Alen Masic]

Hi,

I have a Legion 5 with Ryzen 7, iGPU is AMD, and the dedicated GPU is Nvidia GTX 1650 Ti.
Currently, I'm on switchable graphics but the problem is the same on discrete graphics as well.

In `/sys/class/backlight` I see `amdgpu_bl0 ideapad nvidia_0`. When I use the brightness keys on my laptop then `brightness` file in `ideapad` is updated, but the brightness itself is not updated on the laptop.
The only way to control the brightness is to manually edit the `brightness` file in `amdgpu_bl0`.

First I thought that this is the issue with Nvidia drivers so I reported the issue here: https://forums.developer.nvidia.com/t/brightness-not-working-after-upgrading-to-ubuntu-22-04/224227

But the Nvidia support/devs pointed me here because per their opinion the problem is somewhere in `ideapad-laptop` module.

Btw. I'm on Kubuntu 22.04, and kernel is 5.15.0-46-generic, all updates are installed.