radv: ensure correct outinfo is picked.

radv: ensure correct outinfo is picked.

This struct used to rely on being in a union, it isn't anymore,
so we have to pick the correct outinfo struct now.

This should fix a regression since the union became a struct.

dEQP-VK.tessellation.geometry_interaction.point_size.vertex_set_geometry_set

Fixes: 6078a3bd51 (ac/nir: Allow ac_shader_variant_info to contain info about multiple stages.)
Reviewed-by: Timothy Arceri <tarceri@itsqueeze.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>