For backwards compatibility on Sub-NUMA Cluster (SNC) systems the legacy
files in the mon_L3_XX directories must report the sum of data from each
SNC node sharing that L3 cache instance.
To make this possible, pass the "sumdomains" and "ci" fields from
rmid_read structure as extra arguments to resctrl_arch_rmid_read().
Note that the call from check_limbo() never operates on a "sum" basis,
so pass sumdomains=false, ci=NULL.