- Add conversions to/from little endian for fields that the NIC accesses
by DMA as required.
- Add some bus_dmamap_sync() calls, and correct some existing ones.
- Read the receiver information from the EEPROM in an endian-neutral
manner.
- Load all RX and TX descriptors in a single DMA map up front, and
get the bus addresses of individual descriptors by address arithmetic;
this fixes multiple use of the descriptor tags, which would have
undesired effects.
It seems that xl still does not work on e250 boxen, for reasons which
are not clear yet.
Reviewed by: mux