- Fix broken use of VkImageCreateFlags in various places as an aspect mask
- Be consistent about layout of D+S images. Layout is now [aspect][layer][level].
- Allow fetching an offset into a particular aspect.

Fixes dEQP-VK.pipeline.depth.*

Bug: b/118619338
Change-Id: I46adc9c637882e7144945eaeacce9f087d53caf0
Reviewed-on: https://swiftshader-review.googlesource.com/c/SwiftShader/+/26011Tested-by: Chris Forbes <chrisforbes@google.com>
Presubmit-Ready: Chris Forbes <chrisforbes@google.com>
Kokoro-Presubmit: kokoro <noreply+kokoro@google.com>
Reviewed-by: Alexis Hétu <sugoi@google.com>