This PR uses the VK_EXT_debug_utils extension, but it's only for labeling, so it doesn't rely on the VK_LAYER_KHRONOS_validation functionality.
The functions that do these things are loaded into the runtime as vulkan extensions.
Declare the function pointers in a struct and make them members of vk_context.
Pull Request: https://projects.blender.org/blender/blender/pulls/106098