If the event represents a threshold crossing event, the two
objects hwDot3ahEfmEventThresholdHi and hwDot3ahEfmEventThresholdLo
form an unsigned 64-bit integer yielding the value that was
crossed for the threshold crossing event (for example, 10,
when 11 occurrences happened in 5 seconds while the threshold
was 10). The two objects are combined as:
hwDot3ahEfmEventLogThreshold = ((2^32) * hwDot3ahEfmEventLogThresholdHi)
+ hwDot3ahEfmEventLogThresholdLo
Otherwise, this value is returned as all F's (2^32 - 1) and
adds no useful information.