ACPICA: fix for object premature deletion

Fix for object premature deletion after CopyObject
on Operation Region (BZ 350)

Signed-off-by: Bob Moore <robert.moore@intel.com>
Signed-off-by: Alexey Starikovskiy <alexey.y.starikovskiy@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>