[WebNN EP] Use boolean flags instead of MLTensorUsage

[Honry]

Fixed #22495

We will keep MLTensorUsage until it is removed from Chromium.

[Honry]

@fdwr, @guschmue, PTAL, thanks!

cc/ @huningxin, @egalli

[guschmue]

@Honry, can you resolve the merge conflict

[Honry]

@Honry, can you resolve the merge conflict

Done, pls. take another look!

[fdwr]

/azp run ONNX Runtime Web CI Pipeline,Windows GPU CI Pipeline,Linux Android Emulator QNN CI Pipeline

[fdwr]

/azp run Linux CPU CI Pipeline,Linux CPU Minimal Build E2E CI Pipeline,Linux GPU CI Pipeline,Linux GPU TensorRT CI Pipeline,Linux OpenVINO CI Pipeline,Linux QNN CI Pipeline,MacOS CI Pipeline,Windows ARM64 QNN CI Pipeline,Windows CPU CI Pipeline

[fdwr]

/azp run Windows GPU TensorRT CI Pipeline,onnxruntime-binary-size-checks-ci-pipeline,orttraining-linux-ci-pipeline,orttraining-linux-gpu-ci-pipeline,orttraining-ortmodule-distributed,Windows x64 QNN CI Pipeline,Big Models

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[fdwr]

/azp run Windows GPU CUDA CI Pipeline,Windows GPU DML CI Pipeline,Windows GPU Doc Gen CI Pipeline

[azure-pipelines[bot]]

Azure Pipelines successfully started running 1 pipeline(s).

[azure-pipelines[bot]]

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