[clang] [llvm] [CLANG][OpenMP] Add support for OpenMP6.0 transparent clause (PR #166810)

[Zahira Ammarguellat via llvm-commits]

zahiraam wrote:

@kparzysz, @Meinersbur I am not very familiar with the `OpenMP flang` side of things. Can I have some help with this? It's getting some build issues.
It looks like `flang` has some implementation of the clause, but it takes a scalar as argument instead of the `OMP_*` keywords. See https://github.com/zahiraam/llvm-project/blob/main/flang/include/flang/Parser/parse-tree.h#L4856 and it's use in `flang/test/Parser/OpenMP/transparent-clause.f90`. 
I suppose this implementation needs to change right?

https://github.com/llvm/llvm-project/pull/166810