Allow for all layers in Qwen3.5 architecture to be Gated Deltanet.

[HallerPatrick]

What does this PR do?

Fixes #45146

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[github-actions]

[For maintainers] Suggested jobs to run (before merge)

run-slow: qwen3_5

[Rocketknight1]

Good-natured closing after comments in #45146, but your code looks good so feel free to submit other PRs in future!