net: hns3: make some reusable codes into a function

In hclge_dcb.c, these pair of codes:
	hclge_notify_client(hdev, HNAE3_DOWN_CLIENT);
	hclge_notify_client(hdev, HNAE3_UNINIT_CLIENT);
and
	hclge_notify_client(hdev, HNAE3_INIT_CLIENT);
	hclge_notify_client(hdev, HNAE3_UP_CLIENT);
are called many times, so make them into a function.

Signed-off-by: Yonglong Liu <liuyonglong@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>