Arm backend: Create ethosu directory

[Sebastian-Larsson]

Move EthosU related files to its own directory.

cc @digantdesai @freddan80 @per @zingo @oscarandersson8218

[pytorch-bot]

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✅ You can merge normally! (5 Unrelated Failures)

As of commit 0a982ae with merge base f2f2a9d ():

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

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

• pull / test-models-linux (mobilebert, portable, linux.2xlarge) / linux-job (gh) (trunk failure)
  ##[error]The operation was canceled.
• pull / test-models-linux (mobilebert, xnnpack-quantization-delegation, linux.2xlarge) / linux-job (gh) (trunk failure)
  ##[error]The operation was canceled.
• trunk / test-models-linux-aarch64 (mobilebert, portable, linux.arm64.2xlarge) / linux-job (gh) (trunk failure)
  ##[error]The operation was canceled.
• trunk / test-models-linux-aarch64 (mobilebert, xnnpack-quantization-delegation, linux.arm64.2xlarge) / linux-job (gh) (trunk failure)
  ##[error]The operation was canceled.
• trunk / test-qnn-model (fp32, mb) / linux-job (gh) (trunk failure)
  ##[error]The operation was canceled.

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

[Sebastian-Larsson]

This change affects the file structure and as such I suspect it will affect buck2 builds. Could someone assist in correcting the buck2 TARGETS files? @digantdesai

[zingo]

FYI @mergennachin (as @digantdesai is off)

[digantdesai]

Let me pull it internally, i expect it to cause problems

[facebook-github-bot]

@digantdesai has imported this pull request. If you are a Meta employee, you can view this diff on Phabricator.

[Sebastian-Larsson]

@digantdesai How did it go?

[facebook-github-bot]

@digantdesai has imported this pull request. If you are a Meta employee, you can view this in D77349641.

[digantdesai]

@Sebastian-Larsson - I have a fix. Do you mind if I take over this PR? Or create a new one with buck fixes?

[Sebastian-Larsson]

@digantdesai I don't mind, go for it :)

[digantdesai]

Superseding PR #12338