ACPICA: Fix: Predefined object repair executed only once

This fixes a problem where the code that attempts to repair/convert
an object of incorrect type is only executed on the first time the
predefined method is called. The mechanism that disables warnings
on subsequent calls was interfering with the repair mechanism.
ACPICA BZ 781.

http://acpica.org/bugzilla/show_bug.cgi?id=781

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>