When hns_assemble_skb() returns NULL to skb, no error return code of
hns_nic_clear_all_rx_fetch() is assigned.
To fix this bug, ret is assigned with -ENOMEM in this case.
Reported-by: NTOTE Robot <oslab@tsinghua.edu.cn>
Signed-off-by: NJia-Ju Bai <baijiaju1990@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>