The header uses macros from Xfuncproto.h - right now it just works by pure
accident since consumers of this header indirectly include Xfuncproto.h
by totally different roads. This is a fragile programming style that deserved
to be cleand up.
Signed-off-by: Enrico Weigelt, metux IT consult <info@metux.net>
Part-of: <https://gitlab.freedesktop.org/xorg/xserver/-/merge_requests/1331>