[Whisper, Bart, MBart] Add Flash Attention 2 (#27203)
* add whisper fa2
* correct
* change all
* correct
* correct
* fix more
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* fix more
* Apply suggestions from code review
Co-authored-by: amyeroberts <22614925+amyeroberts@users.noreply.github.com>
* fix more
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* fix more
* fix more
* fix more
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Co-authored-by: amyeroberts <22614925+amyeroberts@users.noreply.github.com>
