bonding: fix active-backup transition

Earlier patch c4adfc82 ("bonding: make speed, duplex setting
consistent with link state") made an attempt to keep slave state
consistent with speed and duplex settings. Unfortunately link-state
transition is used to change the active link especially when used
in conjunction with mii-mon. The above mentioned patch broke that
logic. Also when speed and duplex settings for a link are updated
during a link-event, the link-status should not be changed to
invoke correct transition logic.

This patch fixes this issue by moving the link-state update outside
of the bond_update_speed_duplex() fn and to the places where this fn
is called and update link-state selectively.

Fixes: c4adfc82 ("bonding: make speed, duplex setting consistent
with link state")
Signed-off-by: Mahesh Bandewar <maheshb@google.com>
Reviewed-by: Andy Gospodarek <andy@greyhouse.net>
Signed-off-by: David S. Miller <davem@davemloft.net>