Add FP8 support for Llama3.1-8b

[blzheng]

Motivation

This PR is for the DMR LZ KPI POC. It adds FP8 support for Llama3.1-8B using the recipe from INC, and also supports prompt files in the format shown in this example.

Modifications

Checklist

• Format your code according to the Code Formatting with Pre-Commit.
• Add unit tests as outlined in the Running Unit Tests.
• Update documentation / docstrings / example tutorials as needed, according to Writing Documentation.
• Provide throughput / latency benchmark results and accuracy evaluation results as needed, according to Benchmark and Profiling and Accuracy Results.
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