Switch back to NVIDIA/cutlass, and upgrade to v4.2.1

[jasl]

The issue has been fixed https://github.com/NVIDIA/cutlass/blob/v4.2.1/tools/util/include/cutlass/util/mixed_dtype_utils.hpp#L180-L184

So I switch back to the official repo and upgrade to v4.2.1, which is important for ARM Blackwell

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