The type of OAM cells to discard when usdAtmIfOamCellRxAdminState is
set to oamCellAdminStateDisabled. The value oamCellFilterAlarm discards
received OAM AIS and RDI cells. The value oamCellFilterAll discards all
received OAM cells. Note that when usdAtmIfOamCellRxAdminState is set
to oamCellAdminStateEnabled, this object has no effect.