The enums are the same between the two extensions. The 24-8 packed
depth/stencil format is the only thing provided by the latter.

Remove some redundant code.
Signed-off-by: Chip Davis <cdavis@codeweavers.com>
Signed-off-by: Henri Verbeet <hverbeet@codeweavers.com>
Signed-off-by: Alexandre Julliard <julliard@winehq.org>