[TORCH] Patch cuda stream protocol for older torch

[tqchen]

This PR add patch to update torch to include cuda stream protocol for older version.

[gemini-code-assist]

Summary of Changes

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This pull request addresses compatibility issues with older PyTorch versions by implementing a patch that ensures the __cuda_stream__ protocol is available for torch.cuda.Stream objects. This change is crucial for maintaining consistent behavior and preventing errors when interacting with CUDA streams in environments where older PyTorch installations might lack this specific protocol, thereby improving the robustness of the TVM FFI with PyTorch.

Highlights

• PyTorch Compatibility: Introduced a patch to ensure compatibility with older versions of PyTorch regarding CUDA stream handling.
• CUDA Stream Protocol: Dynamically adds the __cuda_stream__ protocol to torch.cuda.Stream objects if it's not already present, allowing for consistent stream interaction.
• Conditional Patching: The patch is applied conditionally, only if torch.cuda is available and the __cuda_stream__ attribute is missing from torch.cuda.Stream.

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[gemini-code-assist]

Code Review

This pull request adds a patch to support the CUDA stream protocol for older versions of PyTorch. The overall approach of monkey-patching torch.cuda.Stream is correct, but the implementation of the patched method __torch_cuda_stream__ has a critical bug. It hardcodes the device ID to 0, which will cause issues in multi-GPU environments. I've provided a suggestion to fix this.