[llvm] [GlobalISel][LLT] Introduce FPInfo for LLT (Enable bfloat, ppc128float and others in GlobalISel) (PR #155107)

[via llvm-commits]

DenisGZM wrote:

With further diving into different customizable fp types, I think we would better keep something like `APFloatBase::Semantics` instead of `FPVariant` in `LLT`, but this also comes with much higher scope of changes

https://github.com/llvm/llvm-project/pull/155107