ac/surface: enable tile swizzle for mipmapped textures

ac/surface: enable tile swizzle for mipmapped textures

The tile swizzle computation was done after the whole miptree was computed,
but that was too late, because at that point AddrSurfInfoOut contained
information about the smallest miplevel, which is never 2D-tiled.

The correct way is to do the computation before the second level is computed.

Reviewed-by: Dave Airlie <airlied@redhat.com>
Reviewed-by: Nicolai Hähnle <nicolai.haehnle@amd.com>