ControlNet+Adapter pipeline, and ControlNet+Adapter+Inpaint pipeline

[affromero]

What does this PR do?

Fixes #5847 ✅

Adds two custom pipelines: pipeline_stable_diffusion_xl_controlnet_adapter (StableDiffusionXLControlNetAdapterPipeline) and pipeline_stable_diffusion_xl_controlnet_adapter_inpaint (StableDiffusionXLControlNetAdapterInpaintPipeline).

They unify ControlNet and T2IAdapter into a single pipeline, where both methods can be exploited together in a single forward. control_image and adapter_image must be added to the forward call, and also controlnet_conditioning_scale and adapter_conditioning_scale to account for the strength.

I included some visuals in #5847.

The inpainting version follows the changes made in this PR #5527 (review)

I was not sure where to place the pipelines since there are independent subfolders for controlnet and adapter, so I naively put it in the stable_diffusion_xl folder.

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Pipelines: @patrickvonplaten and @sayakpaul

[yiyixuxu]

cc @patrickvonplaten

I think this should go into community folder for now

if there is a lot of usage and we decide to integrate to core I think we can deprecate the controlnet pipelines and adapter pipelines because this should be able to replace them no?

Let me know what you think

[HuggingFaceDocBuilderDev]

The documentation is not available anymore as the PR was closed or merged.

[patrickvonplaten]

Good to merge IMO - wdyt @yiyixuxu ?

[yiyixuxu]

thank you!