Remote tensor enablement via C-API

[atobiszei]

• Enable usage of OpenCL buffers via OVMS C-API
• Enable usage of VA surfaces via OVMS C-API
• Enable setting output buffers for C-API inference to avoid copy
• Add C-API Async inference

Sync does work only with models. The same is true for setting output & remote tensors.

TODO:

• async error handling
• async & model reload/unload compatibility
• add negative tests
• add tests for models with multiple inputs/outputs
• TBD dispose getting context out of loaded model

🛠 Summary

JIRA/Issue if applicable. Describe the changes.

🧪 Checklist

• [ x] Unit tests added.
• [ ] The documentation updated.
• [ ] Change follows security best practices.

[dtrawins]

Can you include in tests swapping the model version while running the inferences?

[atobiszei]

Can you include in tests swapping the model version while running the inferences?

Async compatibility with online modification is not included in this MR as mentioned in description.