Synchronization2 cleanup

[purton]

As the tutorial is using Synchronization2, maybe it would make sense to use vkQueueSubmit2 and VK_STRUCTURE_TYPE_SUBMIT_INFO_2 instead of the old ones?

Also, according to this page, VK_PIPELINE_STAGE_TOP_OF_PIPE_BIT is deprecated with Synchronization2. But it's still in use in one place in the tutorial.

[SaschaWillems]

Thanks for noticing.. A first version of this didn't use sync2, so most prob. a left-over.