Fixing GPU Adapter Count test to be more dynamic and fail resistent

[umfranci]

• The verify_gpu_adapter_count test validates GPU counts by comparing outputs from lsvmbus, lspci, and nvidia-smi commands. However, it relies on a hardcoded list of GPU models and their device IDs to identify GPUs in the lsvmbus output.
• This hardcoded approach fails when testing new GPU models, requiring manual code updates each time a new GPU hardware is released. This creates testing delays, maintenance overhead and increases failure percentage of the test.
• Hence the aim here is to implement dynamic GPU detection to automatically identify new GPU models without manual intervention, while maintaining backward compatibility with existing GPU detection logic.
• Suggested Fix:
  • Primary detection: Continue using the existing hardcoded GPU list for known models
  • Fallback mechanism: When no matches are found in the hardcoded list:
    • Group VMBus devices by their last segment (device ID suffix)
    • Identify GPU device groups where all entries are marked as "PCI Express pass-through"
    • Validate the count matches nvidia-smi output for accuracy
  • Direct counting: Added a new function to get GPU count directly from nvidia-smi command output, eliminating dependency on maintaining a hardcoded GPU model list