Add vulkan backend for stable-diffusion.cpp

[BillyOutlast]

Current versions of stable-diffusion.cpp support the Vulkan backend for image generation, is it possible to update version used in LocalAI to support Vulkan? Thank you!

[mudler]

Makes sense, definitely we can add this.

[BillyOutlast]

Hero!

Thank you so much, this small change will make a world of difference 😊