tg3: Add 57765 phy ID and enable devices.

This patch rounds out the 57765 asic rev support by adding the 57765 phy
ID and entering the 57765 device IDs in the pci table.

Signed-off-by: Matt Carlson <mcarlson@broadcom.com>
Reviewed-by: Michael Chan <mchan@broadcom.com>
Reviewed-by: Benjamin Li <benli@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>