Server: Improve DRI3 implementation

(based on the implementation in TigerVNC 1.14 beta)

- Synchronize pixels between DRI3 pixmaps and their corresponding GBM
  buffer objects on an as-needed basis, in response to specific X11
  operations rather than on a schedule.

- Implement the simpler DRI3 v1 interface rather than DRI3 v2.  This
  avoids the need to implement the get_formats(), get_modifiers(), and
  get_drawable_modifiers() methods.

- Use Pixman (which is SIMD-accelerated) to synchronize pixels.

- Hook the DestroyPixmap() screen method to clean up a pixmap's
  corresponding GBM buffer object if there are no more references to the
  pixmap.

- Hook the CloseScreen() screen method to clean up the GBM device and
  close the DRM render node.

To do:

- Synchronize only the pixels that have changed.

Known issues:

TigerVNC/tigervnc#1772

unix/Xvnc/programs/Xserver/damageext/damageext.c

@@ -1,8 +1,6 @@
 /*
  * Copyright © 2002 Keith Packard
  * Copyright 2013 Red Hat, Inc.
- * Copyright © 2023 Kasm
- * Copyright © 2024 D. R. Commander
  *
  * Permission to use, copy, modify, distribute, and sell this software and its
  * documentation for any purpose is hereby granted without fee, provided that
@@ -32,10 +30,6 @@
 #include "protocol-versions.h"
 #include "extinit.h"
 
-#if defined(DRI3) && defined(TURBOVNC)
-extern void xvnc_dri3_sync_pixmaps_to_bos(void);
-#endif
-
 #ifdef PANORAMIX
 #include "panoramiX.h"
 #include "panoramiXsrv.h"
@@ -103,10 +97,6 @@ DamageExtNotify(DamageExtPtr pDamageExt, BoxPtr pBoxes, int nBoxes)
 
     damageGetGeometry(pDrawable, &x, &y, &w, &h);
 
-#if defined(DRI3) && defined(TURBOVNC)
-    xvnc_dri3_sync_pixmaps_to_bos();
-#endif
-
     UpdateCurrentTimeIf();
     ev = (xDamageNotifyEvent) {
         .type = DamageEventBase + XDamageNotify,