iris: Remove the CCS_D fallback

iris: Remove the CCS_D fallback

Remove the CCS_D fallback logic so that iris doesn't attempt to use a
non-existent surface state for some renders. Also, add an assertion to
catch the issue.

The fallback in iris_resource_render_aux_usage can lead to this problem
because it doesn't account for the fact that surface states created from
resources with the Y_TILED_CCS modifier may only have CCS_E or NONE as
aux usages (due to iris_resource_create_with_modifiers).

Without this change, the next commit would have triggered the fallback
and regressed the following tests on gen9:

* dEQP-EGL.functional.wide_color.window_888_colorspace_srgb
* dEQP-EGL.functional.wide_color.window_8888_colorspace_srgb
* dEQP-EGL.functional.wide_color.pbuffer_888_colorspace_srgb
* dEQP-EGL.functional.wide_color.pbuffer_8888_colorspace_srgb

Reviewed-by: Kenneth Graunke <kenneth@whitecape.org>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/4972>