[llvm] [OpenMP][offload] Add LIBOMPTARGET_KERNEL_EXE_TIME (PR #222105)

[Joseph Huber via llvm-commits]

jhuber6 wrote:

I'm generally in agreements that we should probably push this onto a profiler. I do see that the implicit timestamp AQL gives you is superior performance-wise, but Im wondering if we could hook that up to the existing interface somehow.

https://github.com/llvm/llvm-project/pull/222105