bnx2x: no error when RSS configuration fails

It's possible for VMs with older versions of bnx2x to run over a hypervisor
with latest driver. If a VF in such a VM does not support RSS configuration,
the PF driver in the hypervisor will print an error message to system logs.

This changes the error message into a debug message, as this is very likely
a false alarm for an older VF (i.e., VF manages to work properly; PF simply
cannot configure the additional queues for it).

Signed-off-by: Yuval Mintz <yuvalmin@broadcom.com>
Signed-off-by: Ariel Elior <ariele@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>