The value of pwTemplateIgmpLastMembIntvl specifies
the Max Response Time (in tenths of a second) used in
Group-Specific and Group-Source-Specific Queries sent
in response to 'leave' messages. This is also the
amount of time between Group-Specific Query messages.
This value may be tuned to modify the leave latency of
the network. A reduced value results in reduced time to
detect the loss of the last member of a group.