A value that uniquely identifies the set of
possible IEEE 802.3 types that the MAU could be. If
auto-negotiation is present on this MAU, this object
will map to hpRpMauAutoNegCapability.
Note that a repeater can never actually support the
full-duplex MAU types. The bits for them are
retained to keep the bit values consistent with
ifMauTypeListBits.