update parallel state following Megatron-LM parallel_state.py 2025.1

[1195343015]

1. update parallel state following Megatron-LM parallel_state.py 2025.1
2. add cp argument and cp_group for developing in future
3. fix some small issues (like when world_size or comm_size is 1, there should be no communications)

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[1195343015]

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