net/nfp: modify RSS logic

net/nfp: modify RSS logic

Now NFP NIC support two type of RSS logic, NFP_NET_CFG_CTRL_RSS and
NFP_NET_CFG_CTRL_RSS2, use NFP_NET_CFG_CTRL_RSS2 if NIC capability
support, otherwise use NFP_NET_CFG_CTRL_RSS.

Signed-off-by: Jin Liu <jin.liu@corigine.com>
Signed-off-by: Diana Wang <na.wang@corigine.com>
Signed-off-by: Peng Zhang <peng.zhang@corigine.com>
Signed-off-by: Chaoyong He <chaoyong.he@corigine.com>
Signed-off-by: Niklas Söderlund <niklas.soderlund@corigine.com>