[Flang][OpenMP] Fix negative array indexing with allocatable derived type array maps (#154193)

The main problem is that the previous intermediate map generation for
allocatable members wasn't quite handling negative bounds acccesses
correctly, it seems to require slightly more complicated access using
shape_shift/dimension information. So this more closely mimics what
Flang generates in other cases now.

There is still a path for non-Box types to go down the old route for the
moment, so it is possible we may still have issues with negative bounds
in these cases. But, that's better in another PR if we come across it,
instead of too much change in this one.

0 files changed, 0 insertions, 0 deletions