Flash Transformers modeling backend support (#2913)
* add transformers_flash
* inits
* switch version to make it work
* Update Makefile-flash-att-v2
* Update Makefile-flash-att-v2
* Update Makefile-flash-att-v2
* Update Makefile-flash-att-v2
* Update Makefile-flash-att-v2
* Update Makefile-flash-att-v2
* runnable version
* working
* push change
* fix high dim
* init
* default
* latest transformers changes
* revert
* simplify check
* remove flag
* improve type hints + required args
* Update based on transformers PR
* small fix
* Remove Warpers for Processor
* fix compatibility version issue
* raise error if needed
* Simplify with monkey patch
* revert + style + minor improvements
* update comment
* device check
* move the import to avoid device issue
* Update __init__.py
* check for non-native models
* oupsi
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Co-authored-by: System administrator <root@ip-10-90-0-159.ec2.internal>