Check the VF RSS offload flag and ignore relative operation when
iavf hash uninit to avoid reset/close error.
Fixes: 7be10c3004be ("net/iavf: add RSS configuration for VF")
Cc: stable@dpdk.org
Signed-off-by: Steve Yang <stevex.yang@intel.com>
Acked-by: Qi Zhang <qi.z.zhang@intel.com>