This involves extending our fake extension a bit to allow for additional
querying and passing of modifier information. The added bits are
intended to look a lot like the draft of VK_EXT_image_drm_format_modifier.
Once the extension gets finalized, we'll simply transition all of the
structs used in wsi_common to the real extension structs.
Reviewed-by: Daniel Stone <daniels@collabora.com>
f5433e4d6c