Refactor attention for SigLIP based models (#36981)
* Update Siglip attention implementation
* Update tests for Siglip
* Remove one level of indentation
* Update test to be more specific
* Fixup
* Idefics2
* Idefics3
* Emu3
* SmolVLM
* Phi4 (just init small update)
* Idefics2 (test fix)
* Update siglip2 tests
* Update eager
* trigger
* Clean up
* Transfer inputs to device in test
* Fixing test
* Fixing test
* Revert contiguous
* Remove unused is_flash_attn_2_available
* Move flaky to specific models
