[llvm] [Offload][UnitTests] Build device code as C++ (PR #151714)

[Joseph Huber via llvm-commits]

jhuber6 wrote:

> My preference in that case would still be macros, but I've not looked into this so if you have a template solution that is cleaner I'm happy with that.

C/C++ doesn't make a huge difference, just requires the C ABI on the symbols you look up. Usually a template function is easier to read than a bunch of macros.

https://github.com/llvm/llvm-project/pull/151714