[flang] Merge pull request flang-compiler/f18#631 from flang-compiler/jpr-fix-589

Prevent result symbol to be converted into function when they are called

Original-commit: flang-compiler/f18@464310a1e3b8cc222b0069c213de01c4c4561eaf
Reviewed-on: https://github.com/flang-compiler/f18/pull/631