Added Windows cmd to count GPU devices

[xylieong]

🛠️ PR Summary

_{Made with ❤️ by Ultralytics Actions}

🌟 Summary

Enhanced GPU count compatibility for YOLOv5 on Windows.

📊 Key Changes

• Updated device_count() in utils/torch_utils.py to support Windows.
• Modified the assertion to allow the function to run on both Linux and Windows systems.
• Adapted the command within device_count() to differentiate between Linux and Windows environments.

🎯 Purpose & Impact

• 🎯 Purpose: Expand the usability of the YOLOv5 by allowing it to correctly count available CUDA devices on Windows, not just Linux.
• 💻 Impact: Windows users can now leverage YOLOv5 with improved support for their GPU environments, leading to better accessibility and convenience for a broader user base.

[github-actions]

👋 Hello @xylieong, thank you for submitting a YOLOv5 🚀 PR! To allow your work to be integrated as seamlessly as possible, we advise you to:

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[glenn-jocher]

@xylieong PR is merged. Thank you for your contributions to YOLOv5 🚀 and Vision AI ⭐