Implementation Kohya Hires.fix for Auto1111 webui

Stop step - at which sampling step disable fix, increase at higher resolution

Depth - on which layer fix will be applied

Downsampling scale - decrease at higher resolution, helps preserve composition at very high resolutions

Upsampling scale - increasing can slightly improve quality at cost of VRAM

Source:

https://gist.github.com/kohya-ss/3f774da220df102548093a7abc8538ed