net: fec: use netif_tx_disable() rather than netif_stop_queue()

net: fec: use netif_tx_disable() rather than netif_stop_queue()

We use netif_stop_queue() in several places where we want to ensure that
the start_xmit function is not running.  netif_stop_queue() is not
sufficient to achieve that - it merely sets a flag to indicate that the
transmit queue(s) should not be run.

netif_tx_disable() gives this guarantee, since it takes the transmit
queue lock while marking the queue stopped.  This will wait for the
transmit function to complete before returning.

Acked-by: Fugang Duan <B38611@freescale.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>