bnx2x: Move netif_napi_add to the open call

Move netif_napi_add for all queues from the probe call to the open call, to
avoid the case that napi objects are added for queues that may eventually not
be initialized and activated. With the former behavior, the driver could crash
when netpoll was calling ndo_poll_controller.

Signed-off-by: Merav Sicron <meravs@broadcom.com>
Signed-off-by: Dmitry Kravkov <dmitry@broadcom.com>
Signed-off-by: Eilon Greenstein <eilong@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>