Arm backend: Add amin support for Ethos-U55

[AdrianLundell]

Amin support was enabled in Vela 5.0.0

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

[pytorch-bot]

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❌ 1 Awaiting Approval, 2 New Failures, 1 Cancelled Job, 2 Unrelated Failures

As of commit 868f44c with merge base 2165b5a ():

AWAITING APPROVAL - The following workflow needs approval before CI can run:

• periodic (gh)

NEW FAILURES - The following jobs have failed:

• pull / unittest-arm-backend-with-no-deps (test_pytest_ops_tosa) / linux-job (gh)
  RuntimeError: Command docker exec -t 738c23810299efd1a3dd26e42f3a364d9aac2288bd33715b01c52ec2fec954bb /exec failed with exit code 1
• pull / unittest-editable / macos / macos-job (gh)
  backends/xnnpack/test/ops/test_conv2d.py::TestConv2d::test_fp16_conv2d

CANCELLED JOB - The following job was cancelled. Please retry:

• pull / android / run-emulator (gh)
  ##[error]The operation was canceled.

BROKEN TRUNK - The following jobs failed but were 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.

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