IB/mlx4: Build the port IBoE GID table properly under bonding

When scanning netdevices we need to check a few more conditions and
cases to build the IBoE GID table properly.  For example, under
bonding we must make sure that when a port is down, the bond IP
address isn't programmed as a GID, since doing so will cause failure
with IB core flows that selects ports by GID.

Signed-off-by: Moni Shoua <monis@mellanox.co.il>
Signed-off-by: Or Gerlitz <ogerlitz@mellanox.com>
Signed-off-by: Roland Dreier <roland@purestorage.com>