net/mlx5: fix RSS enablement

net/mlx5: fix RSS enablement

PMD create some default control rules with RSS action
if it's not isolated mode.

However whether default control rules need to do RSS or not should be
controlled by device configuration, the mq_mode of rxmode configuration
in specific.

In another word, only when mq_mode is configured with ETH_MQ_RX_RSS_FLAG
set, then RSS is needed for default rules.

Fixes: c64ccc0eca2f ("mlx5: fix overwritten RSS configuration")
Cc: stable@dpdk.org
Signed-off-by: Xiaoyu Min <jackmin@mellanox.com>
Signed-off-by: Viacheslav Ovsiienko <viacheslavo@mellanox.com>
Acked-by: Viacheslav Ovsiienko <viacheslavo@mellanox.com>
Acked-by: Matan Azrad <matan@mellanox.com>