Drivers implementing descriptor buffers will want to allocate and free
descriptors with the layout for embedded samplers, so we need a hook to
allow them to free any GPU buffers.
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/19849>
There's some tricky stuff in here with properly handling Vulkan
allocation scopes and reference counting. Probably best to do it once.
Also, this means that common code can now take references to descriptor
set layouts which seems useful.
Reviewed-by: Lionel Landwerlin <lionel.g.landwerlin@intel.com>
Reviewed-by: Jesse Natalie <jenatali@microsoft.com>
Reviewed-by: Boris Brezillon <boris.brezillon@collabora.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/17286>
