[Xcb] only one type of iterator available for xcb_xv_list_image_formats

[Christoph Pfister]

Hi,

Unlike for e.g. xcb_format_t where you have xcb_setup_pixmap_formats,
xcb_setup_pixmap_formats_length and xcb_setup_pixmap_formats_iterator
there's only xcb_xv_list_image_formats_format_length and
xcb_xv_list_image_formats_format_iterator.

What about xcb_xv_list_image_formats_format ?

Thanks in advance

Christoph