Current count, from CMTS initialization, of initial maintenance
minislots defined for this upstream logical channel. This count
includes all minislots for IUC3 assigned to a broadcast or multicast
SID on the logical channel.
This is the 64 bit version of
docsIfCmtsUpChnlCtrTotalCntnInitMaintMslots,
and will not be accessible to SNMPv1 managers.
Support for this object is optional. If the object is not supported,
A value of zero is returned.