A flag denoting if the lease of a pool is
unlimited.
The value means:
invalid(0)- The lease of the network address that clients be assigned is finite,
the period is decided by hwDHCPSGlobalPoolLeaseDay,hwDHCPSGlobalPoolLeaseHour and
hwDHCPSGlobalPoolLeaseMinute
unlimited(1)-The lease of the network address that clients be assigned is infinite