net/bonding: always update bonding link status

net/bonding: always update bonding link status

When the first ETH_LINK_UP slave is added to a bonding device, it is
immediately activated.  If these are polling slaves, there will be a
later link state event, when last_link_status doesn't match link_status.
But because this slave is already activated, the bonding device's link
status isn't updated.

To fix this, we always attempt to update the bonding device's link status
in the link state change callback.

Fixes: 46fb43683679 ("bond: add mode 4")
Cc: stable@dpdk.org
Signed-off-by: Chas Williams <chas3@att.com>