[flang] [llvm] [flang][OpenMP] Avoid early returns, NFC (PR #117231)

[Krzysztof Parzyszek via llvm-commits]

kparzysz wrote:

There seemed to be a merge/rebase error, where a duplicate definition of a template function was added instead of replacing the previous one.

Sorry, I didn't notice it.

https://github.com/llvm/llvm-project/pull/117231