When the HNS driver loaded, always have an error print:
"netif_napi_add() called with weight 256"

This is because the kernel checks the NAPI polling weights
requested by drivers and it prints an error message if a driver
requests a weight bigger than 64.

So use NAPI_POLL_WEIGHT to fix it.
Signed-off-by: Yonglong Liu <liuyonglong@huawei.com>
Signed-off-by: Peng Li <lipeng321@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>