feat: Expose BF16 precision in TensorRT

[dwyatte]

What does the PR do?

BF16 was added to the ONNX runtime TensorRT EP in microsoft/onnxruntime#24743, this PR should expose it to Triton's ONNX backend

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• build
• ci
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• feat
• fix
• perf
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Related PRs:

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Where should the reviewer start?

src/onnxruntime.cc

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Background

See microsoft/onnxruntime#24743 for more info

Related Issues: (use one of the action keywords Closes / Fixes / Resolves / Relates to)

• closes GitHub issue: BF16 support for integrated TensorRT precision mode server#5959

[whoisj]

Adding @yinggeh to review this. I'm not as familiar w/ ONNX->TRT as I should be.

[yinggeh]

Adding @yinggeh to review this. I'm not as familiar w/ ONNX->TRT as I should be.

Not familiar either but looks like a small change. I will take a look today.

[whoisj]

@dwyatte, please make sure you've completed the contribution requirements: https://github.com/triton-inference-server/server?tab=readme-ov-file#contributing. Thank you.

[dwyatte]

@dwyatte, please make sure you've completed the contribution requirements: https://github.com/triton-inference-server/server?tab=readme-ov-file#contributing. Thank you.

@whoisj Block (my corporate entity) has previously completed the CLA here, but let me know if I need to personally submit something too

[yinggeh]

LGTM if the change is indeed this simple.

[yinggeh]

Please update PR title and description using the template https://github.com/triton-inference-server/server/blob/main/.github/PULL_REQUEST_TEMPLATE/pull_request_template_external_contrib.md. Fill n/a for any field doesn't apply

[dwyatte]

Please update PR title and description using the template https://github.com/triton-inference-server/server/blob/main/.github/PULL_REQUEST_TEMPLATE/pull_request_template_external_contrib.md. Fill n/a for any field doesn't apply

@yinggeh Done!

[yinggeh]

@whoisj Is our client eligible for contributing now?