Add WavLM- & Wav2Vec2ForAudioFrameClassification support (#611)
* Add WavLMForXVector support
* fix model docs
* Add WavLMForAudioFrameClassification
* Add missing wWav2Vec2ForAudioFrameCl.
* Add doc comment
* Add doc string wav2vec2
* update comment
* make example like python
* Update src/models.js
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Co-authored-by: Joshua Lochner <admin@xenova.com>