ACPICA: Simplify internal operation region interface

Changed address parameter to a simple offset. This removes the
need for the caller to access the region object to obtain the
physical address.

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