net/iavf: fix command after PF reset

net/iavf: fix command after PF reset

If PF reset is finished but VF reset is pending, VF should no need to
send any invalid cmd to PF. That would avoid mass unexpected behaviors
affecting the robust.

Fixes: 22b123a36d07 ("net/avf: initialize PMD")
Fixes: 9e03acd726cf ("net/iavf: fix flow access")
Cc: stable@dpdk.org
Signed-off-by: Jeff Guo <jia.guo@intel.com>
Tested-by: Hailin Xu <hailinx.xu@intel.com>
Acked-by: Qi Zhang <qi.z.zhang@intel.com>