scpi-dmm: add four-wire resistance to list of 34405A MQs

scpi-dmm: add four-wire resistance to list of 34405A MQs

Although the 34405A does not support this function, other Agilent
protocol using meters do (currently 34465A, very probably others which
are about to get added in the future).

It's assumed that announcing the availability of that MQ for a set of
meters while only some of them support it is preferrable over exploding
numbers of copies of tables which only slightly vary among each other.