anv: Return number of layers/levels attached to anv_image

Don't check the auxiliary surface's ISL surf in order to return the
surface levels/layers instead we can return the anv_image parameter.

Signed-off-by: Sagar Ghuge <sagar.ghuge@intel.com>
Reviewed-by: Nanley Chery <nanley.g.chery@intel.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/2942>
1 file changed