A disabled device doesn't have a sprite (less so a sprite->win) and triggers
a NULL-pointer dereference on shutdown when all active grabs are released as
part of the cleanup.
Fix this by checking for sprite being non-null and setting the focus window
to the NullWindow if it is. The rest of the patch just attempts to make
things more readable.
Signed-off-by: Peter Hutterer <peter.hutterer@who-t.net>
Reviewed-by: Keith Packard <keithp@keithp.com>