ACPICA: Predefined name repair: fix NULL package elements

For the predefined methods that return fixed-length packages
(or subpackages), attempt repair for a NULL element. Create an
Integer of value 0, a NULL String, or a zero-length buffer as
appropriate.

http://www.acpica.org/bugzilla/show_bug.cgi?id=818

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>