net: Fix call to ->change_rx_flags(dev, IFF_MULTICAST) in dev_change_flags()

net: Fix call to ->change_rx_flags(dev, IFF_MULTICAST) in dev_change_flags()

[ upstream commit: 0e91796eb46e29edc791131c832a2232bcaed9dd ]

Am I just being particularly dim today, or can the call to
dev->change_rx_flags(dev, IFF_MULTICAST) in dev_change_flags() never
happen?

We've just set dev->flags = flags & IFF_MULTICAST, effectively. So the
condition '(dev->flags ^ flags) & IFF_MULTICAST' is _never_ going to be
true.

Signed-off-by: David Woodhouse <dwmw2@infradead.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Chris Wright <chrisw@sous-sol.org>