[][Add Ethernet HW LRO support depending on hw_capability]

[Description]
Add Ethernet HW LRO support and related debug interface
depending on hw_capability.

---------Debug method 1 - Auto learn table---------
- Dump aggregated flows:
	$ cat /proc/mtketh/hw_lro_auto_tlb
- Modify MAX_AGGREGATED_CNT:
	$ echo 0 [setting] > /proc/mtketh/hw_lro_auto_tlb
- Modify MAX_AGG_TIME:
	$ echo 1 [setting] > /proc/mtketh/hw_lro_auto_tlb
- Modify AGE_TIME:
	$ echo 2 [setting] > /proc/mtketh/hw_lro_auto_tlb
- Modify AUTO_LEARN_LRO_ELIGIBLE_THRESHOLD:
	$ echo 3 [setting] > /proc/mtketh/hw_lro_auto_tlb
- Enable/Disable LRO:
	$ echo 4 [1/0] > /proc/mtketh/hw_lro_auto_tlb

---------Debug method 2 - per LRO ring statistics--------
- Dump each LRO rings' statistics, which includes packet count,
  packet length, flush reason, etc.
	$ cat /proc/mtketh/hw_lro_stats

[Release-log]
N/A

Change-Id: I2359ac177b81077bb7c95ee5fae2f32aadda521f
Reviewed-on: https://gerrit.mediatek.inc/c/openwrt/feeds/mtk_openwrt_feeds/+/4588327
4 files changed