If the event represents a threshold crossing event, the two
objects h3cDot3OamEventThresholdHi and h3cDot3OamEventThresholdLo
form an unsigned 64-bit integer yielding the value that was
crossed for the threshold crossing event (e.g. 10, when 11
occurrences happened in 5 seconds while the threshold was 10).
The two objects are combined as:
h3cDot3OamEventLogThreshold = ((2^32) * h3cDot3OamEventLogThresholdHi)
+ h3cDot3OamEventLogThresholdLo
Otherwise, this value is returned as all F's (0xFFFFFFFF) and
adds no useful information.