This object indicates which metrics are valid for the traffic
flow:
'lostPkts'
If this bit is set to '1', then the corresponding
instance of cfmIpCbrMetricsLostPkts is valid.
'mediaRateVariation'
If this bit is set to '1', then the corresponding
instances of cfmIpCbrMetricsMlrScale,
cfmIpCbrMetricsMlrPrecision, and cfmIpCbrMetricsMlr are
valid.