[llvm] [GlobalISel] use constexpr LLT types when creating ISel data (PR #191574)

[Michal Paszkowski via llvm-commits]

michalpaszkowski wrote:

@stanleygambarin Thanks for the patch! I am fine with either solution. I don't see any downsides to the workaround apart from the fact that it is a workaround and the original problem is still present. The workaround is somewhat self-contained and we could always go with the alternative later.

Going with the alternative would solve the actual problem, but will force each backend with `ExtendedLLT=true` to make changes and use the types explicitly. This is not a problem now in the upstream, but might potentially be for some backends in the downstream that rely on PR #155107. 

CC @DenisGZM @tgymnich I am also adding reviewers from the #155107 in case they have any thoughts/preferences.



https://github.com/llvm/llvm-project/pull/191574