[OpenMP][FIX] Do not use TBAA in type punning reduction GPU code PR46156

When we implement OpenMP GPU reductions we use type punning a lot during
the shuffle and reduce operations. This is not always compatible with
language rules on aliasing. So far we generated TBAA which later allowed
to remove some of the reduce code as accesses and initialization were
"known to not alias". With this patch we avoid TBAA in this step,
hopefully for all accesses that we need to.

Verified on the reproducer of PR46156 and QMCPack.

Reviewed By: ABataev

Differential Revision: https://reviews.llvm.org/D86037