bonding: Fix some issues for fail_over_mac

The parameter fail_over_mac only affect active-backup mode, if it was set to active or follow and works with other modes, just like RR or XOR mode, the bonding could not set all slaves to the master's address, it will cause the slave could not work well with master.

So set the fail_over_mac to none if the mode is not active-backup and slight optimization for bond_set_mac_address().

v1->v2: According Jay's suggestion, that we should permit setting an option
at any time, but only have it take effect in active-backup mode, so I add mode checking together with fail_over_mac during enslavement and rebuild the patches.

Regards
Ding

Ding Tianhong (3):
bonding: Set the correct value to fail_over_mac at enslavement
bonding: only affect active-backup mode when fail_over_mac is not
none
bonding: cleanup some redundant code and wrong variables

 drivers/net/bonding/bond_main.c | 26 ++++++++++++++------------
 1 file changed, 14 insertions(+), 12 deletions(-)

1.8.0