net: hns3: remove unnecessary variable in hclge_get_mac_vlan_cmd_status()

The local variable return_status in hclge_get_mac_val_cmd_status()
is useless. So this patch returns the error code directly, instead of
using this variable. Also, replace some '%d' with '%u' in
hclge_get_mac_val_cmd_status().

Signed-off-by: Jian Shen <shenjian15@huawei.com>
Reviewed-by: Peng Li <lipeng321@huawei.com>
Signed-off-by: Huazhong Tan <tanhuazhong@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>