[llvm] [AMDGPU] Generalize generic-target numeric property validation (PR #223177)

[Shilei Tian via llvm-commits]

shiltian wrote:

> The old validator required every frontend-visible feature on the generic target to appear as the exact same feature record on every covered GPU. It therefore rejected the generics `FeatureLDSAllocGranularity1280` when checking gfx942, which has `FeatureLDSAllocGranularity512`.

Ah, I think I ran into this issue yesterday. I do think the validator has a wrong assumption here. I think a feature of a generic target must come from at least one of the targets it covers. It doesn't make sense to assume that all of those targets need to support every feature. I have a fresh example that counters that assumption, and we can't do anything about it on our side. It has nothing to do with numeric values at all, so the scope of what this PR is doing is really limited and can't resolve the fundamental issue with our generic targets.

https://github.com/llvm/llvm-project/pull/223177