[llvm] [offload] Extract OMPT out of PluginInterface (PR #221726)

[Jan Patrick Lehr via llvm-commits]

jplehr wrote:

Thank you for looking at this. I will review these changes in detail tomorrow (currently on mobile). 

Here is a link to the WIP port of our downstream OMPT tracing support that adds a generic profiler infrastructure: https://github.com/llvm/llvm-project/pull/200165 

https://github.com/llvm/llvm-project/pull/221726