asahi: Fix compressed ZLS handling
We need to use the compression buffer's layer stride when calculating the compression buffer addresses, this is different from the primary buffer's layer stride. To make this change, the address calculation code is refactored for ZLS, since otherwise this commit would be adding tomato sauce to spaghetti code.
Fixes (with depth/stencil compression enabled):
dEQP-GLES31.functional.texture.multisample.samples_4.use_texture_depth_2d_array
Signed-off-by: Alyssa Rosenzweig alyssa@rosenzweig.io