fix scale_shift_factor being on cpu for wan and ltx (#12347)
* wan fix scale_shift_factor being on cpu
* apply device cast to ltx transformer
* Apply style fixes
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Co-authored-by: Dhruv Nair <dhruv.nair@gmail.com>
Co-authored-by: github-actions[bot] <github-actions[bot]@users.noreply.github.com>