A cpeExtPsePortLldpEntry entry contains the LLDP
based 802.3at DLL power classification characteristics for
a particular PSE and the PD attached to it.
A PSE has its entry here when all of the following conditions
are satisfied:
- The LLDP power classification is globally enabled.
- It has a PD attached.
- LLDP is the operational power negotiation protocol between
the PSE and the PD attached.