bonding: add Speed/Duplex information to /proc/net/bonding/bond

Effect:
 Slave Interface: eth5
 MII Status: up
 Speed: 10000 Mbps
 Duplex: full
 Link Failure Count: 0
 Permanent HW addr: XX:XX:XX:XX:XX:XX
 Slave queue ID: 0
Signed-off-by: NKrzysztof Piotr Oledzki <ole@ans.pl>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

drivers/net/bonding/bond_main.c

@@ -3353,6 +3353,8 @@ static void bond_info_show_slave(struct seq_file *seq,
 	seq_printf(seq, "\nSlave Interface: %s\n", slave->dev->name);
 	seq_printf(seq, "MII Status: %s\n",
 		   (slave->link == BOND_LINK_UP) ?  "up" : "down");
+	seq_printf(seq, "Speed: %d Mbps\n", slave->speed);
+	seq_printf(seq, "Duplex: %s\n", slave->duplex ? "full" : "half");
 	seq_printf(seq, "Link Failure Count: %u\n",
 		   slave->link_failure_count);