RSS hash configure get API (i40e_dev_rss_hash_conf_get()) didn't check
the return value of i40e_get_rss_key().
i40e_dev_rss_hash_conf_get() will return success even getting RSS hash
key failed. This patch fixes the issue.
Fixes: d0a349409bd7 ("i40e: support AQ based RSS config")
Cc: stable@dpdk.org
Signed-off-by: Qiming Yang <qiming.yang@intel.com>
Reviewed-by: Ferruh Yigit <ferruh.yigit@intel.com>