bnx2x: Fix invalid memory access in rss hash config path.

Rx hash/filter table configuration uses rss_conf_obj to configure filters
in the hardware. This object is initialized only when the interface is
brought up.
This patch adds driver changes to configure rss params only when the device
is in opened state. In port disabled case, the config will be cached in the
driver structure which will be applied in the successive load path.

Please consider applying it to 'net' branch.

Signed-off-by: Sudarsana Reddy Kalluru <Sudarsana.Kalluru@cavium.com>
Signed-off-by: David S. Miller <davem@davemloft.net>