vulkan: Fix pipeline layout allocation scope
The lifetime of Mesa's vk_pipeline_layout
may exceed that of the VkPipelineLayout
object as other objects on the device may hold references to it. In other places in vk_pipeline_layout
and vk_descriptor_set_layout
, the device allocation scope is used with this pattern, but there was an inconsistency in vk_pipeline_layout_zalloc
, which is fixed by this merge request.