[flang] [llvm] [flang][openmp] Adds Parser and Semantic Support for Interop Construct, and Init and Use Clauses. (PR #120584)

[Kiran Chandramohan via llvm-commits]

https://github.com/kiranchandramohan commented:

@swatheesh-mcw Thanks for this patch. Could you rebase?

For error messages, we usually have the OpenMP constructs, clauses or reserved terms in caps. Could you update the error messages and tests appropriately?

Could you also add a Lowering test that checks for the TODO message. eg: https://github.com/llvm/llvm-project/blob/main/flang/test/Lower/OpenMP/Todo/dispatch.f90

https://github.com/llvm/llvm-project/pull/120584