tu: Implement VK_EXT_image_2d_view_of_3d

This is already allowed by the gallium driver, which uses the same code
for image layout and image views, so everything Just Works and the tests
pass. radv doesn't enable the sampler feature, but I don't see any
reason it wouldn't work and the tests pass.

Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/16806>
2 files changed