bonding: use ether_addr_equal_unaligned for bond addr compare

Use possibly more efficient ether_addr_equal_64bits
to instead of memcmp.

Modify the MAC_ADDR_COMPARE to MAC_ADDR_EQUAL, this looks more
appropriate.

The comments for the bond 3ad is too old, cleanup some errors
and warming.

Suggested-by: Joe Perches <joe@perches.com>
Signed-off-by: Ding Tianhong <dingtianhong@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>