anv/image: Refactor choice of isl_tiling_flags_t

anv/image: Refactor choice of isl_tiling_flags_t

Instead of choosing the tiling flags inside make_surface(), which is
called once per aspect in a loop, and which chooses the same tiling for
each aspect, choose the tiling flags exactly once before entering the
aspect loop.

Reviewed-by: Jason Ekstrand <jason@jlekstrand.net>
Reviewed-by: Lionel Landwerlin <lionel.g.landwerlin@intel.com>