bonding: Fix slave selection bug.

The returned slave is incorrect, if the net device under check is not
charged yet by the master.
Signed-off-by: Hillf Danton <dhillf@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
(cherry picked from commit af3e5bd5)
Signed-off-by: Willy Tarreau <w@1wt.eu>

drivers/net/bonding/bonding.h

@@ -236,11 +236,11 @@ static inline struct slave *bond_get_slave_by_dev(struct bonding *bond, struct n
 
 	bond_for_each_slave(bond, slave, i) {
 		if (slave->dev == slave_dev) {
-			break;
+			return slave;
 		}
 	}
 
-	return slave;
+	return 0;
 }
 
 static inline struct bonding *bond_get_bond_by_slave(struct slave *slave)