bonding: print information about speed and duplex seen by the driver

before:
 bonding: bond0: link status definitely up for interface eth5
 bonding: bond0: link status definitely up for interface eth0

after:
 bonding: bond0: link status definitely up for interface eth5, 100 Mbps full duplex.
 bonding: bond0: link status definitely up for interface eth0, 100 Mbps full duplex.

Signed-off-by: Krzysztof Piotr Oledzki <ole@ans.pl>
Signed-off-by: David S. Miller <davem@davemloft.net>