Some uses of the preprocessor can result in multiple target regions on the

Some uses of the preprocessor can result in multiple target regions on the
same line. Cases such as those in the associated lit tests, can now be
supported.

This adds a 'Count' field to TargetRegionEntryInfo to differentiate
regions with the same source position.

The OffloadEntriesInfoManager routines are updated to maintain a count of
regions seen at a location. The registration of regions proceeds that same as
before, but now the next available count is always determined and used in the
offload entry.

Fixes: https://github.com/llvm/llvm-project/issues/52707

Differential Revision: https://reviews.llvm.org/D134816