[LLVMCPU] Add missing f64 musl builtins for ONNX operations - #24953

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@Prajit-Rahul, thanks for the PR! A couple asks:

• Please rewrite the PR description yourself, as per the accepted policy. The current LLM-written description makes the change harder to understand (e.g. the "Testing" section is completely unnecessary, and without looking at the code, it's unclear how WASM and CPU targets relate to one another in this scope)
• Please note the CI failures in the ONNX ops suite

@Prajit-Rahul, thanks for the PR! A couple asks:

• Please rewrite the PR description yourself, as per the accepted policy. The current LLM-written description makes the change harder to understand (e.g. the "Testing" section is completely unnecessary, and without looking at the code, it's unclear how WASM and CPU targets relate to one another in this scope)
• Please note the CI failures in the ONNX ops suite

Thanks for the feedback. I’ve revised the description to clarify that LLVMCPU uses the generic wasm32/wasm64 musl bitcode libraries to supply math functions for native CPU targets and removed the Testing section.

The ONNX O0 and O2 jobs failed because six tests still listed as expected compilation failures now compile and run successfully. I have also removed those six entries from both expected-failure lists in the follow-up commit. I’ll check the O0 and O2 results when the new CI jobs run.