st/nir: Call nir_lower_clip_cull_distance_arrays().
Today, st always sets LowerCombinedClipCullDistance, causing the GLSL IR lowering to run, giving us vec4 arrays. I would like to disable this and instead run the NIR lowering so that we get compact float arrays instead. Calling the new pass is a noop if the GLSL IR pass has already run, so it's safe to call the pass unconditionally. Reviewed-by: Timothy Arceri <firstname.lastname@example.org>