Add complete support for 5714/5715. These chips are very similar to
5780 so the changes are very trivial. A TG3_FLG2_5780_CLASS flag is
added to identify these chips.
Signed-off-by: NMichael Chan <mchan@broadcom.com>
Signed-off-by: NJeff Garzik <jgarzik@pobox.com>