Status for the physical link diagnosis operation between
the Master device and the current selected EP device.
The diagnosed results include the SNR/LineRate/PacketErrorRate/RxPower
for both the DnLink:'Transmit'(Tx)-to-EP and
UpLink:'Receive'(Rx)-from-EP operation.
The SNMP manager can set the eocBrEPPhyDiagAction value
to activate(1) to start the diagnosis procedure. The status
(eocBrEPPhyDiagStatus) will go from inProgress(1) status back
to the initial normalOrComplete(0) status.