set kernel parameters permanently

[benneti]

Hey, I am currently trying out ChimeraOS on my HTPC and like it so far. I only have a small problem, my system regularly hangs which I previously fixed by adding amdgpu.noretry=0 iommu=soft as kernel parameters, I was able to do that as well however I have the feeling that this manual intervention will be necessary on every update. A permanent solution would be appreciated!