- put a dev_id field in struct net_device, so that it uses space that
   would be wasted by padding otherwise.
 - if this fields is non-null let ipv6_generate_eui64 use the algorithm
   from the QETH code to generate an EUI that's different for each
   OS instance.  See code comments for details.
Signed-off-by: David S. Miller <davem@davemloft.net>