Add Aimv2 model (#36625)
* Model skelton
* changes
* temp push
* changes
* Added support for aimv2-native
* More changes
* More changes
* Stupid mistake correction
* Added config and refactor
* Added vison model
* update
* Refactor for lit variant
* Added Text Model
* Minor fixes
* nits
* update
* Preliminary tests
* More fixes
* Updated tests 🤗
* Refactor
* Updated testcase
* Updated config
* make fixup
* more fixes
* Bug fix and updates
* deadcode
* Fixes
* nit
* up
* Happy CI ✅
* Reduce LOC
* nit
* nit
* make style
* return_dict refactor
* bug fix
* fix
* doc update
* nit
* make fixup
* Minor update
* _init_weigths modifcation
* update tests
* Minor fixes post review
* Update w.r.t GradientCheckpointingLayer
* docs update
* update
* nit
* Use more Modular 😉
* Change name from AIMv2 to Aimv2
* Nit
* make style
* Add model doc pointer
* make style
* Update model doc section
* updates
* Modify attn mask and interface
* update test
* Final change
* Utilize flash and flex attn
* keep attn mask
* camelcase model name in test file
* Fix docstring
* Fix config warning finally and create_causal_mask
* disable torchscript
* remove unused arg
* remove from tests
* balance model size for tests
* fix device
* tests
* tests
* flaky test
* fix import
---------
Co-authored-by: Cyril Vallez <cyril.vallez@huggingface.co>
Co-authored-by: Cyril Vallez <cyril.vallez@gmail.com>
