NXP backend: Enable adaptive_avg_pool2d with new Neutron flow.

[MartinPavella]

Summary

This PR reflects the new Neutron requirements for the enablement of adaptive_avg_pool_2d in NXP backend,

Test plan

Unit tests provided.

cc @robert-kalmar @JakeStevens @digantdesai @rascani

[pytorch-bot]

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❌ 1 New Failure, 1 Unrelated Failure

As of commit 4fed4de with merge base b04cc65 ():

NEW FAILURE - The following job has failed:

• pull / unittest-editable / windows / windows-job (gh)
  Process completed with exit code 1.

BROKEN TRUNK - The following job 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)
  backends/xnnpack/test/recipes/test_xnnpack_recipes.py::TestXnnpackRecipes::test_8a4w_recipe

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[MartinPavella]

@novak-vaclav as per usual, cannot add you as a reviewer but please feel free to have a look :)