Arm backend: Update while_loop in control-flow quant folding

[SaoirseARM]

Summary

Update quantization annotation of while loop to ensure when additional inputs are provided such as threshold, quantization parameters are different.

• add node.meta["additional_inputs"] to ensure when threshold is used different quantization parameters are used.
• Update to quant folding to merge these if different

cc @digantdesai @freddan80 @per @zingo @oscarandersson8218 @mansnils @Sebastian-Larsson @robell

[pytorch-bot]

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❌ 3 New Failures, 2 Cancelled Jobs, 1 Pending, 4 Unrelated Failures

As of commit 33bfa4f with merge base 32a6cec ():

NEW FAILURES - The following jobs have failed:

• Build Presets / apple (pybind) / build (gh)
  The process '/opt/homebrew/bin/git' failed with exit code 128
• pull / android / run-emulator (gh)
  The process '/usr/local/lib/android/sdk/platform-tools/adb' failed with exit code 224
• pull / test-multimodal-linux (gemma3-4b) / linux-job (gh)
  RuntimeError: Command docker exec -t 54e2be94dddce886b7114a8d4c673cfc79defb4d580f8a8142398c56705fd8b4 /exec failed with exit code 139

CANCELLED JOBS - The following jobs were cancelled. Please retry:

• trunk / test-models-macos-coreml (mobilebert) / macos-job (gh)
  ##[error]The operation was canceled.
• trunk / test-models-macos-cpu (llama2, xnnpack-quantization-delegation) / macos-job (gh)
  ##[error]The operation was canceled.

FLAKY - The following job failed but was likely due to flakiness present on trunk:

• trunk / test-llama-runner-linux (bf16, portable, linux.2xlarge, executorch-ubuntu-22.04-clang12) / linux-job (gh) (matched linux rule in flaky-rules.json)
  The runner has received a shutdown signal. This can happen when the runner service is stopped, or a manually started runner is canceled.

BROKEN TRUNK - The following jobs failed but was present on the merge base:

👉 Rebase onto the `viable/strict` branch to avoid these failures

• pull / unittest / windows / windows-job (gh) (trunk failure)
  ##[error]The operation was canceled.
• pull / unittest-editable / windows / windows-job (gh) (trunk failure)
  ##[error]The operation was canceled.
• trunk / unittest-release / windows / windows-job (gh) (trunk failure)
  ##[error]The operation was canceled.

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[SaoirseARM]

@pytorchbot label ciflow/trunk

[SaoirseARM]

@pytorchbot label 'partner: arm'

[SaoirseARM]

@pytorchbot label "release notes: arm"

[zingo]

OK to merge but if possible/OK after #18948 or make sure it does not conflict with that PR.