Auto wrap modules in ZeRO 3 based on _no_split_modules as FSDP

[oraluben]

What does this PR do?

When using FSDP with auto_wrap, transformers will try to wrap modules defined in _no_split_modules. This can reduce overhead of small modules.

DeepSpeed have similar mechanism for ZeRO3, but need to be explicit called by user (set_z3_leaf_modules).
This PR automatically set leaf module based on _no_split_modules.

Some point that might need discussion:

1. Should we only enable this when enabling torch.compile or not;
2. how to disable this feature as there's no fsdp_config='auto_wrap' for this case

Related: microsoft/DeepSpeed#6683

Fixes # (issue)

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