The value of vRtrIgmpHostMaxGroups specifies the maximum number of groups
for which IGMP can have local receiver information based on received
IGMP reports on this subscriber host. When this configuration is changed
dynamically to a value lower than currently accepted number of groups,
the groups that are already accepted are not deleted. Only new groups
will not be allowed. When this object has a value of 0, there is no
limit to the number of groups.