layers: Simplify DESCRIPTOR_POOL_STATE
layers: Simplify DESCRIPTOR_POOL_STATE

Just use safe_* here rather than copying things manually.

KhronosGroup/Vulkan-LoaderAndValidationLayers,KhronosGroup/Vulkan-LoaderAndValidationLayers,KhronosGroup/Vulkan-LoaderAndValidationLayers,KhronosGroup/Vulkan-LoaderAndValidationLayers