bugfix: uninitialized pPointer in miPointerGetPosition ifndef MPX
adding DeviceIntPtr parameter to ScreenRec's cursor functions.
cleanup of miPointer code to use same scheme in each function
dix: MPHasCursor() function determines checking whether to invoke
cursor rendering.
animcur: adding DeviceIntPtr parameter to cursor functions but animcur relies
on the core pointer right now.
xfixes: adding DeviceIntPtr parameter to cursor functions but xfixes relies on
the core pointer right now.
rac: adding DeviceIntPtr parameter to cursor functions but RAC relies on
the core pointer right now.
ramdac: adding DeviceIntPtr parameter to cursor functions but ramdac relies on
the core pointer right now.
1c7568b8a1