When nfp_pf_create_dev() is cleaning up, it does not correctly set
the dev_private variable to NULL, which will lead to a double free.
Fixes: ef28aa96e53b ("net/nfp: support multiprocess")
Cc: stable@dpdk.org
Signed-off-by: Yunjian Wang <wangyunjian@huawei.com>
Acked-by: Heinrich Kuhn <heinrich.kuhn@netronome.com>