ACPICA: Fix possible memory leak for Scope ASL operator

Using Scope(\) to change the scope to the root could cause a
single object memory leak.

Signed-off-by: Lin Ming <ming.m.lin@intel.com>
Signed-off-by: Bob Moore <robert.moore@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>

diff --cc drivers/acpi/acpica/dswload.c
Simple merge