[llvm] [OFFLOAD][OMP] Move OpenMP kernel argument processing from plugins (PR #213867)

[Kevin Sala Penades via llvm-commits]

https://github.com/kevinsala approved this pull request.

LGTM.

Thanks, it's a good first step. We can then start moving other logic to libomptarget easier.

https://github.com/llvm/llvm-project/pull/213867