ionic: tame the watchdog timer on reconfig

ionic: tame the watchdog timer on reconfig

[ Upstream commit b59eabd23ee53e8c3492602722e1697f9a2f63ad ]

Even with moving netif_tx_disable() to an earlier point when
taking down the queues for a reconfiguration, we still end
up with the occasional netdev watchdog Tx Timeout complaint.
The old method of using netif_trans_update() works fine for
queue 0, but has no effect on the remaining queues.  Using
netif_device_detach() allows us to signal to the watchdog to
ignore us for the moment.

Fixes: beead698b173 ("ionic: Add the basic NDO callbacks for netdev support")
Signed-off-by: Shannon Nelson <snelson@pensando.io>
Acked-by: Jonathan Toppins <jtoppins@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>