OpenVINO metadata fix2

[xylieong]

🛠️ PR Summary

_{Made with ❤️ by Ultralytics Actions}

🌟 Summary

Improved compatibility within the OpenVINO export functionality and metadata file handling.

📊 Key Changes

• Modified the way the metadata file name is constructed during OpenVINO export in export.py
• Ensured correct Path object handling when checking for the existence of a metadata file in models/common.py

🎯 Purpose & Impact

• 🛠 Ensures metadata files are correctly named and stored, preventing potential export errors for OpenVINO users.
• ⚙️ Improves overall reliability when integrating YOLOv5 models with Intel's OpenVINO toolkit, which could lead to smoother deployment on various platforms, including those requiring FP16 or FP32 precision formats.
• 🚀 Users can expect more robust model export experiences, particularly when working with different data types and deploying across diverse hardware.

[xylieong]

Modified metadata to be in the folder {pt_model_path}/{model name}_openvino_model

[glenn-jocher]

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