intel: rework system RAM memory restrictions
Update: new version of the series! Not an RFC anymore.
Unfortunately we can't make everyone happy, but my main motivation here is that certain workloads can actually work with my system, and the only thing stopping them from working is this restriction is we inflict in ourselves. Examples: Deathloop on 16GB TGL, certain graphics settings of Spider-Man Remastered on my 16GB non-upgradeable-RAM LNL, Renderdoc.
Of course, this always brings the risk that running too many things at once may awake the OOM monster, but IMHO, completely preventing certain workloads from working is too high of a price to pay in a situation where you can just use /usr/bin/kill something. Still, I'm open to discussion here. We don't need to apply all patches in the series.
See the big discussion below.