Arm backend: Correct per channel axis for transpose conv

[mansnils]

Adjust per-channel weight axis for conv_transpose2d based on group(s).

The corrected axis is propagated to:

• QuantizationSpec
• QAT fake-quant constructors wrapped in PartialWrapper
• Non-QAT observer/fake-quant constructors (via with_args)

cc @digantdesai @SS-JIA @freddan80 @per @zingo @oscarandersson8218 @Sebastian-Larsson @robell

[pytorch-bot]

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❌ 1 Awaiting Approval, 3 New Failures, 3 Unrelated Failures

As of commit ba71305 with merge base 389ea94 ():

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

• periodic (gh)

NEW FAILURES - The following jobs have failed:

• pull / test-models-linux (mv2, xnnpack-quantization-delegation, linux.2xlarge) / linux-job (gh)
  AttributeError: module 'urllib' has no attribute 'URLopener'
• pull / test-samsung-models-linux / linux-job (gh)
  RuntimeError: Command docker exec -t 543683f172aa6815ea269d18047865855da850184789bdaa1a82215400aa4958 /exec failed with exit code 1
• pull / test-samsung-quantmodels-linux / linux-job (gh)
  RuntimeError: Command docker exec -t 3408d1c3591ce18b189b73a079a04c500bbd124eb7eebbf6531c66519cbcb7a7 /exec failed with exit code 1

FLAKY - The following job failed but was likely due to flakiness present on trunk:

• pull / unittest-editable / windows / windows-job (gh) (detected as infra flaky with no log or failing log classifier)

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

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

• pull / unittest / macos / macos-job (gh) (trunk failure)
  AttributeError: '_OpNamespace' 'mkldnn' object has no attribute '_is_mkldnn_acl_supported'
• pull / unittest-editable / macos / macos-job (gh) (trunk failure)
  AttributeError: '_OpNamespace' 'mkldnn' object has no attribute '_is_mkldnn_acl_supported'

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[pytorch-bot]

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