net/bonding: Enable bonding to enslave non ARPHRD_ETHER

This patch changes some of the bond netdevice attributes and functions
to be that of the active slave for the case of the enslaved device not being
of ARPHRD_ETHER type. Basically it overrides those setting done by ether_setup(),
which are netdevice **type** dependent and hence might be not appropriate for
devices of other types. It also enforces mutual exclusion on bonding slaves
from dissimilar ether types, as was concluded over the v1 discussion.

IPoIB (see Documentation/infiniband/ipoib.txt) MAC address is made of a 3 bytes
IB QP (Queue Pair) number and 16 bytes IB port GID (Global ID) of the port this
IPoIB device is bounded to. The QP is a resource created by the IB HW and the
GID is an identifier burned into the HCA (i have omitted here some details which
are not important for the bonding RFC).

Signed-off-by: Moni Shoua <monis at voltaire.com>
Signed-off-by: Or Gerlitz <ogerlitz at voltaire.com>
Acked-by: Jay Vosburgh <fubar@us.ibm.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>