[PATCH net-next] tg3: Set real_num_rx_queues for non-multiq devs

Commit 2ddaad39 entitled "tg3: Use
netif_set_real_num_{rx,tx}_queues()" added a new call to
netif_set_real_num_rx_queues in tg3_enable_msix().  This call also needs
to be added to the legacy path to correctly reflect the actual number of
rx queues.

Signed-off-by: Matt Carlson <mcarlson@broadcom.com>
Acked-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>