Arm backend: Relax Qwen3-VL 2B text BF16 tolerance

[Sebastian-Larsson]

Raise the TOSA BF16 tolerance for the Qwen3-VL 2B instruct text model.

cc @digantdesai @freddan80 @per @zingo @oscarandersson8218 @mansnils @robell @rascani

[pytorch-bot]

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❌ 3 New Failures, 1 Cancelled Job, 1 Pending

As of commit 92887aa with merge base fa49f8f ():

NEW FAILURES - The following jobs have failed:

• pull / unittest / linux / linux-job (gh)
  RuntimeError: Command docker exec -t 3f2d8eec5456629909486cc6880c2aaa5823fed34aec4631022280b141331ffb /exec failed with exit code 1
• pull / unittest-editable / linux / linux-job (gh)
  RuntimeError: Command docker exec -t e0e70bfa46ec0f92775932a9c775d953d4cb047981ec22309949afbc05ceb843 /exec failed with exit code 1
• trunk / unittest-release / linux / linux-job (gh)
  RuntimeError: Command docker exec -t 73b29461ffc291b9502e101877701249898699487dfb9e4672648dcc85d2e790 /exec failed with exit code 1

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

• pull / unittest-nxp-neutron / linux-job (gh)
  ##[error]The operation was canceled.

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