Support LMSDiscreteScheduler in LDMPipeline (#891)
* Support LMSDiscreteScheduler in LDMPipeline
This is a small change to support all schedulers such as LMSDiscreteScheduler in LDMPipeline.
What's changed
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* Add the `scale_model_input` function before `step` to ensure correct denoising (L77)
* Add "scale the initial noise by the standard deviation required by the scheduler"
* run `make style`
Co-authored-by: Anton Lozhkov <anton@huggingface.co>
