mi: drop now obsolete mioverlay.h

This used to be part of public API, but no (known) driver ever
using it, nor any exported functions left. The only internal consumer
(mioverlay.c) also gone now, so it's time to drop this file.

Signed-off-by: Enrico Weigelt, metux IT consult <info@metux.net>
Part-of: <https://gitlab.freedesktop.org/xorg/xserver/-/merge_requests/1503>

hw/xfree86/sdksyms.sh

@@ -200,7 +200,6 @@ cat > sdksyms.c << EOF
 #include "mizerarc.h"
 #include "micoord.h"
 #include "mistruct.h"
-#include "mioverlay.h"
 
 
 /* randr/Makefile.am */

mi/meson.build

@@ -32,7 +32,6 @@ hdrs_mi = [
   'migc.h',
   'mi.h',
   'miline.h',
-  'mioverlay.h',
   'mipointer.h',
   'mipointrst.h',
   'mistruct.h',

mi/mioverlay.h

@@ -1,12 +0,0 @@
-
-#ifdef HAVE_DIX_CONFIG_H
-#include <dix-config.h>
-#endif
-
-#ifndef __MIOVERLAY_H
-#define __MIOVERLAY_H
-
-typedef void (*miOverlayTransFunc) (ScreenPtr, int, BoxPtr);
-typedef Bool (*miOverlayInOverlayFunc) (WindowPtr);
-
-#endif                          /* __MIOVERLAY_H */