Arm backend: Fix transposed conv lowering

[Christoffer-JL]

Avoid accidentally slicing transpose convolutions.

Input slicing is used for regular convolutions to trim unused edge regions for TOSA lowering, but that is not valid for transpose convolutions. Shrinking the input to a transpose convolution changes the expanded output shape and can break output_padding cases.

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

[pytorch-bot]

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❌ 1 New Failure, 1 Pending, 4 Unrelated Failures

As of commit c072133 with merge base 69989b7 ():

NEW FAILURE - The following job has failed:

• Lint / link-check / lint-urls (gh)
  Process completed with exit code 1.

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

• trunk / test-models-macos-coreml (ic4) / macos-job (gh) (matched macos rule in flaky-rules.json)
  File doesn't exist

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)
  ##[error]The operation was canceled.
• pull / unittest-editable / macos / macos-job (gh) (trunk failure)
  ##[error]The operation was canceled.
• trunk / unittest-release / macos / macos-job (gh) (trunk failure)
  ##[error]The operation was canceled.

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