[llvm] [OpenMP] Port the OpenMP device runtime to direct C++ compilation (PR #123673)

[Jan Patrick Lehr via llvm-commits]

jplehr wrote:

Do you plan to have a follow-up that addresses the concerns about the explicit address space numbers? I too think it would be easier to read if some sort of enum is used instead of plain numbers.

https://github.com/llvm/llvm-project/pull/123673