Some old PF drivers don't let VFs allocate counters, in that case, use
the sink counter so the VF can load and operate properly.

Fixes: 6de5f7f6 ('net/mlx4_core: Allocate default counter per port')
Reported-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: Or Gerlitz <ogerlitz@mellanox.com>
Signed-off-by: Eran Ben Elisha <eranbe@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>