[code-reflection] RFR: ONNX LLM example implementation

[Adam Sotona]

ONNX LLM example implementation

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Commit messages:
 - LlamaDemo implementation

Changes: https://git.openjdk.org/babylon/pull/495/files
  Webrev: https://webrevs.openjdk.org/?repo=babylon&pr=495&range=00
  Stats: 386 lines in 9 files changed: 298 ins; 78 del; 10 mod
  Patch: https://git.openjdk.org/babylon/pull/495.diff
  Fetch: git fetch https://git.openjdk.org/babylon.git pull/495/head:pull/495

PR: https://git.openjdk.org/babylon/pull/495