asahi: Use 2D array staging resources for cube/3D

asahi: Use 2D array staging resources for cube/3D

Staging resources need to be linear for efficient CPU side mapping. This is a
problem for access to 3D and cube textures, since we don't have linear 3D
textures or linear cube textures. But we do have linear 2D array textures, which
can be reshaped to the same effect. So use a 2D array staging resource even for
3D textures and cube maps.

Signed-off-by: Alyssa Rosenzweig <alyssa@rosenzweig.io>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/22891>