net: hns3: add interface hclge_tm_bp_setup

Provide a common interface to complete the back pressure settings
of all enabled TCs. So other functions directly call this interface
to complete the corresponding operation.

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