qeth: Accurate ethtool output

For OSA devices that support the QUERY_CARD_INFO command, supply
accurate data based on the card type, port mode and link speed
via the 'ethtool' interface.

Signed-off-by: Eugene Crosser <Eugene.Crosser@ru.ibm.com>
Signed-off-by: Frank Blaschka <frank.blaschka@de.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>