Make sure that kstat chains are updated for each fetch request
Clusters which use kstat to fetch its metrics must make sure
that chains are properly oiled before walking them otherwise
some instance domains may not be updated (disks were found AWOL
after boot) - hide the kstat_ctl pointer inside data.c and make
sure it can only be accessed if it has been updated properly.
Make sure that kstat chains are updated for each fetch request
Clusters which use kstat to fetch its metrics must make sure
that chains are properly oiled before walking them otherwise
some instance domains may not be updated (disks were found AWOL
after boot) - hide the kstat_ctl pointer inside data.c and make
sure it can only be accessed if it has been updated properly.