Cortex-M backend: Updates to enable mobilenet-v3 test

[SaoirseARM]

Summary

• Ensures conv2d are channels last.
• Updates maximum and minimum to not broadcast scalars
• Adds decomposition of adaptive avg_pool2d

cc @freddan80 @per @zingo @oscarandersson8218 @digantdesai

[pytorch-bot]

🔗 Helpful Links

🧪 See artifacts and rendered test results at hud.pytorch.org/pr/pytorch/executorch/16337

• 📄 Preview Python docs built from this PR

Note: Links to docs will display an error until the docs builds have been completed.

❌ 2 New Failures, 1 Unrelated Failure

As of commit fb1b5ba with merge base c61b2ed ():

NEW FAILURES - The following jobs have failed:

• pull / unittest-arm-backend-with-no-fvp (test_pytest_models) / linux-job (gh)
  RuntimeError: Command docker exec -t ebad944444677e869b2b8466c8a1882c61f97f9f69346807379f28d2346d6feb /exec failed with exit code 1
• trunk / test-arm-backend (test_pytest_models_ethosu_fvp) / linux-job (gh)
  RuntimeError: Command docker exec -t dad7e10e8c070123077e5ef646e7a0d3a0ae99f894bde1ac522a2804a7dbd157 /exec failed with exit code 1

UNSTABLE - The following job is marked as unstable, possibly due to flakiness on trunk:

• pull / android / run-emulator (gh) (#16137)
  Timeout waiting for emulator to boot.

This comment was automatically generated by Dr. CI and updates every 15 minutes.

[SaoirseARM]

@pytorchbot label ciflow/trunk

[SaoirseARM]

@pytorchbot label 'partner: arm'

[SaoirseARM]

@pytorchbot label "release notes: none"