Arm backend: Remove unused python module tosautil

[martinlsm]

cc @freddan80 @per @zingo @oscarandersson8218 @digantdesai

[pytorch-bot]

🔗 Helpful Links

🧪 See artifacts and rendered test results at hud.pytorch.org/pr/pytorch/executorch/16646

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❌ 3 New Failures, 1 Unrelated Failure

As of commit b976423 with merge base 642f5c8 ():

NEW FAILURES - The following jobs have failed:

• pull / test-llama-runner-linux (bf16, custom, linux.2xlarge, executorch-ubuntu-22.04-clang12) / linux-job (gh)
  RuntimeError: Command docker exec -t 398ebf0d3f2e96b9b3431f72b937cd69047ea1d43783f26b1e13cb786b6d24d1 /exec failed with exit code 1
• pull / test-llama-runner-linux (fp32, xnnpack+custom+qe, linux.2xlarge, executorch-ubuntu-22.04-clang12) / linux-job (gh)
  RuntimeError: mmap can only be used with files saved with torch.save(stories110M.pt, _use_new_zipfile_serialization=True), please torch.save your checkpoint with this option in order to use mmap.`
• Test CUDA Builds / test-models-cuda (conv1d) / linux-job (gh)
  RuntimeError: Command docker exec -t 46a0360fb4db721bff558bd095965b6d418b193cc159695e12d7fb1912ca7c08 /exec failed with exit code 1

BROKEN TRUNK - The following job failed but were present on the merge base:

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

• pull / android / run-emulator (gh) (trunk failure)
  The process '/usr/bin/sh' failed with exit code 255

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[martinlsm]

@pytorchbot label ciflow/trunk

[martinlsm]

@pytorchbot label "partner: arm"

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[Copilot]

Pull request overview

This pull request removes the unused tosautil Python module from the Arm backend test directory. The module appears to have been previously created but was never integrated or used in the codebase.

Changes:

• Removed the backends/arm/test/tosautil/__init__.py file entirely

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[zingo]

OK to merge if all Arm backend tests PASS when they have finished running!