ACPICA: Performance enhancement for ACPI package objects.

This change greatly increases the performance of package objects
within the interpreter. It changes the processing of reference
counts for packages by optimizing for the most common case where
the package subobjects are either integers, strings, or buffers.
Increases the performance of the ASLTS test suite by 1.5X.
Chao Guan. ACPICA BZ 943.
https://www.acpica.org/bugzilla/show_bug.cgi?id=943

Signed-off-by: Chao Guan <chao.guan@intel.com>
Signed-off-by: Bob Moore <robert.moore@intel.com>
Signed-off-by: Lv Zheng <lv.zheng@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>