port reset cause crash when ports are not stopped. Fixed by refusing the
reset when port is not stopped.
Fixes: 97f1e196799f ("app/testpmd: add port reset command")
Cc: stable@dpdk.org
Signed-off-by: Shougang Wang <shougangx.wang@intel.com>
Acked-by: Bernard Iremonger <bernard.iremonger@intel.com>