feat(rocm-support): support mamba2 on rocm

[almersawi]

Supporting Mamba2 models in ROCm faces two issue:

• XFormersMetadata and FlashAttentionMetadata are not available in ROCm, which raises this issue 13678
• After fixing the first issue, the model is loaded to the GPU, but fails in the warmup with exception:
  AttributeError: '_OpNamespace' '_C' object has no attribute 'causal_conv1d_fwd'

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