tg3: Fix DIDs, Enable 5717 support

This patch fixes the 5717 variant device ID enumerations and adds those
DIDs to the PCI ID table.

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