[][kernel][common][eth][Add RSS ring adjustment for the ethtool]

[Description]
Add RSS ring adjustment for the ethtool.

[Usage]
- Show RSS ring parameters
  # ethtool -x ethX
- Change RSS Rx rings weight under uniform distribution
  # ethtool --set-rxfh-indir ethX equal [num]
- Change RSS Rx rings weight under non-uniform distribution
  # ethtool --set-rxfh-indir ethX weight [w0] [w1] [w2] ...

If without this patch, user can't use ethtool to configure parameters
for the RSS rings.

[Release-log]
N/A


Change-Id: I42491c0fc7289b049cf90ea7366c4bb0adf41082
Reviewed-on: https://gerrit.mediatek.inc/c/openwrt/feeds/mtk_openwrt_feeds/+/7671884
3 files changed