[][Refine Ethernet t-put bound for MT7981]

[Description]
Refactor and refine Ethernet t-put bound issue for MT7981.

This patch includes two major changes:
1. "Re-organize the mapping relationship between queue & sch"
   Currently, the sw data path is adjusted as below
      * CPU(eth0) --> QDMA queue0 --> QDMA sch0 --> GMAC1
      * CPU(eth1) --> QDMA queue8 --> QDMA sch1 --> GMAC2

2. "Disable bridge netfilter module by default"
   After mtkhnat module is loaded to system, mtkhnat init
   script will automatically disable bridge netfilter module
   in order to reduce high cpu usage.
   Then, whenever HQoS is activated, bridge netfilter module
   will be enabled to allow skb being marked. In that way,
   HQoS can properly operate as before.

If without this patch, there is a 1500M performance bound situation
on Ethernet LAN->WAN sw path.

[Release-log]
N/A

Change-Id: I5c4f78e33f449bc64ca17a071378976e21b59865
Reviewed-on: https://gerrit.mediatek.inc/c/openwrt/feeds/mtk_openwrt_feeds/+/5457061
2 files changed