net: hns3: optimize converting dscp to priority process of hns3_nic_select_queue()

Currently, when function hns3_nic_select_queue() converts dscp to priority,
it calls an indirect callback ae_algo->ops->get_dscp_prio to get priority.

However as function hns3_nic_select_queue() is in fast path, the indirect
call may cause degradation of performance. For optimization, this patch
moves dscp_app_cnt and dscp_prio from struct hclge_tm_info to struct
hnae3_knic_private_info, so they can be used in both hclge and hns3 layers.

Signed-off-by: Guangbin Huang <huangguangbin2@huawei.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>