virtio_net: Fix error handling in virtnet_restore()

stable inclusion
from linux-4.19.198
commit 845ae8523f5a9ecfdbed48b485cb4ffae71df95b

--------------------------------

[ Upstream commit 3f2869ca ]

Do some cleanups in virtnet_restore() when virtnet_cpu_notif_add() failed.

Signed-off-by: Xie Yongji <xieyongji@bytedance.com>
Link: https://lore.kernel.org/r/20210517084516.332-1-xieyongji@bytedance.com


Acked-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Yang Yingliang <yangyingliang@huawei.com>