Arm backend: Add testing/support for Inception_v4 and w2l for Ethos-U85

[zingo]

Summary

Inception_v4 and w2l for Ethos-U85 Inception_v3/4, w2l and resnet18/50 for TOSA

Make it possible to override default runtime timeout per test

This also split up GitHub testing in a few separate runners to speed up the testing as it takes longer then 60min.

Fixes #9602 This also fix #9602 where arm unittest didn't build Executorch with EXECUTORCH_BUILD_ARM_BAREMETAL enabled

Test plan

Improve the unit and model testing for Arm backend in github with this patch.

cc @digantdesai @freddan80 @per @oscarandersson8218

[pytorch-bot[bot]]

:link: Helpful Links

:test_tube: See artifacts and rendered test results at hud.pytorch.org/pr/pytorch/executorch/10517

• :page_facing_up: Preview Python docs built from this PR

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

:hourglass_flowing_sand: 2 Pending, 2 Unrelated Failures

As of commit cceef97d58b1e446bcf9ef2da6c109357342dd8c with merge base 17b933f68f35d9d429947fb70aad0710e74f5ddb ():

FLAKY - The following jobs failed but were likely due to flakiness present on trunk:

• trunk / test-huggingface-transformers (HuggingFaceTB/SmolLM2-135M) / linux-job (gh) (matched linux rule in flaky-rules.json) The process '/usr/bin/git' failed with exit code 128
• trunk / test-models-linux-aarch64 (mv2, portable, linux.arm64.2xlarge) / linux-job (gh) (matched linux rule in flaky-rules.json) The process '/usr/bin/git' failed with exit code 128

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

[zingo]

Hi @digantdesai and @mergennachin in this PR I have splitted up the Arm jobs into a few more runners. Aim is to not take such huge amount of time as in the (currently) 3 jobs. E.g. now they take around 1h before this patch.