[OpenMP][Offload] Automatically map indirect function pointers (#71462)

We already have all the information to automatically map function
pointers that have been declared as `indirect` declare target by the
user. This is just enabling and testing the functionality by looking
through the one level of indirection.

GitOrigin-RevId: 2d739f13d49363dd55867e1d8cda80d92d617675
2 files changed