[WebNN EP] Support LRN operator

[miaobin]

WebNN doesn't provide dedicate op for LRN, use a couple of WebNN ops to emulate it in WebNN EP: pow -> transpose -> pad -> averagePool -> transpose -> mul -> add -> pow -> div @Honry @fdwr PTAL, thanks!

[miaobin]

Updated the code based on comments. Please take another look, thanks a lot! @Honry @fdwr

[miaobin]

Thank you for your patient review @Honry @fdwr . Updated the code and please take another look. Thanks a lot!

[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 CUDA CI Pipeline,Windows GPU DML CI Pipeline,Windows GPU Doc Gen 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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