[Feature] Support IP-Adapter Plus (#5915)
* Support IP-Adapter Plus
* fix format
* restore before black format
* restore before black format
* generic
* Refactor PerceiverAttention
* format
* fix test and refactor PerceiverAttention
* generic encode_image
* keep attention implementation
* merge tests
* encode_image backward compatible
* code quality
* fix controlnet inpaint pipeline
* refactor FFN
* refactor FFN
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Co-authored-by: YiYi Xu <yixu310@gmail.com>
