Arm backend: Fix missing init in VGFSetup

[Erik-Lundell]

As documented at
https://vkdoc.net/man/VkDataGraphPipelineSessionBindPointRequirementARM .stype of VkDataGraphPipelineSessionBindPointRequirementARM should alway be set to
VK_STRUCTURE_TYPE_DATA_GRAPH_PIPELINE_SESSION_BIND_POINT_REQUIREMENT_ARM

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

[pytorch-bot]

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❌ 1 New Failure, 3 Unrelated Failures

As of commit 41ee96c with merge base b69cbcd ():

NEW FAILURE - The following job has failed:

• pull / test-multimodal-linux (gemma3-4b) / linux-job (gh)
  RuntimeError: Command docker exec -t 89c926c96a84d197ad06a29690b166f3d6f6a7207152bee57840464da1b2d4bf /exec failed with exit code 139

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 / 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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