ACPICA: Clarify/rename some root table descriptor fields

Original fields were not very descriptive and led to maintenance
problems.  New fields should help to understand the existing code.

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>
6 files changed