Among other things, this gave me an excuse to fix all the bugs (hah!) in vk_graphics_pipeline_state for use with pipeline libraries.
This is on top of !17644 (merged). +@llandwerlin for core Vulkan bits since he reviewed it the first time around and +@zmike for lavapipe. I did a full CTS run on my desktop and this has the same passes/fails as main. (There are currently some conditional rendering flakes on main)