[PATCH xserver] xwayland: Fix use after free of cursors

[Olivier Fourdan]

> Sometimes, Xwayland will try to use a cursor that has just been freed,
> leading to a crash when trying to access that cursor data either in
> miPointerUpdateSprite() or elsewhere.
> [...]

Right, I think I have to withdraw this patch, because it probably doesn't fix the issue...

I still believe the problem finds its root in xwl_xy_to_window() but I still haven't found an appropriate fix.

Sorry about that,
Olivier