nft-qos: add new package

This is the nftables implementation for qos on OpenWrt,
Currently, it has below features:

* Static QoS : setting limit rate for devices or global network.

* Dynamic/Auto QoS : setting limit rate according to the network
  bandwidth and adjust itself automatically (hotplug event).

* Traffic Priority : this feature is like traffic shaping under tc,
  it uses ingress hook to handle to packets here.

Signed-off-by: Rosy Song <rosysong@rosinson.com>

net/nft-qos/files/nft-qos-dynamic.hotplug

@@ -0,0 +1,40 @@
+#!/bin/sh
+#
+# Copyright 2018 rosysong@rosinson.com
+#
+
+. /lib/functions.sh
+. /lib/nft-qos/core.sh
+. /lib/nft-qos/dynamic.sh
+
+NFT_QOS_DYNAMIC_ON=
+
+qosdef_validate_section_dynamic() {
+	local limit_enable limit_type
+
+	uci_validate_section nft-qos default default \
+		'limit_enable:bool:0' \
+		'limit_type:maxlength(8)'
+
+	[ $limit_enable -eq 1 -a \
+	  "$limit_type" = "dynamic" ] && \
+	    NFT_QOS_DYNAMIC_ON="y"
+}
+
+
+logger -t nft-qos-dynamic "ACTION=$ACTION, MACADDR=$MACADDR, IPADDR=$IPADDR, HOSTNAME=$HOSTNAME"
+
+case "$ACTION" in
+	add | update | remove)
+		qosdef_validate_section_dynamic
+		[ -z "$NFT_QOS_DYNAMIC_ON" ] && return
+
+		qosdef_init_env
+		qosdef_flush_dynamic
+
+		qosdef_init_header
+		qosdef_init_dynamic
+		qosdef_init_done
+		qosdef_start
+		;;
+esac