mal_probe crash

[Sean MacLennan]

With Linus' latest git, mal_probe crashes. It calls netif_napi_add with
the first parameter NULL. This was ok since the parameter, a net
device, was only used if CONFIG_NETPOLL was set.

Now it is always de-referenced. A quick check shows that ibm_newemac is
the only driver that passed NULL as the first parameter to this call in
2.6.28.

I don't really follow ibm_newemac changes, so the patch may be waiting
to be applied. This is really just a heads up.

Cheers,
   Sean