Add option to disable rewriting index hints in default global save plan (#105861)
With distributed checkpointing in PyTorch/XLA SPMD, the WriteItem index hints should not be modified when creating the global plan. In order to reuse the default planner logic for checkpoint metadata creation, we need to make the behavior of rewriting index hints optional.
Pull Request resolved: https://github.com/pytorch/pytorch/pull/105861
Approved by: https://github.com/kumpera
