net: hns3: fix race conditions between reset and module loading & unloading

When loading or unloading module, it should wait for the reset task
done before it un-initializes the client, otherwise the reset task
may cause a NULL pointer reference.

Signed-off-by: Huazhong Tan <tanhuazhong@huawei.com>
Signed-off-by: Peng Li <lipeng321@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>