T6121: Extend config-sync for QoS and system options

Extent the service config-sync for sections:
 - qos interface
 - qos policy
 - system conntrack
 - system flow-accounting
 - system option
 - system sflow
 - system static-host-mapping
 - system sysctl

(cherry picked from commit 9d5ad17)

interface-definitions/service_config-sync.xml.in

@@ -344,6 +344,25 @@
                   </leafNode>
                 </children>
               </node>
+              <node name="qos">
+                <properties>
+                  <help>Quality of Service (QoS)</help>
+                </properties>
+                <children>
+                  <leafNode name="interface">
+                    <properties>
+                      <help>Interface to apply QoS policy</help>
+                      <valueless/>
+                    </properties>
+                  </leafNode>
+                  <leafNode name="policy">
+                    <properties>
+                      <help>Service Policy definitions</help>
+                      <valueless/>
+                    </properties>
+                  </leafNode>
+                </children>
+              </node>
               <node name="service">
                 <properties>
                   <help>System services</help>
@@ -435,6 +454,49 @@
                   </leafNode>
                 </children>
               </node>
+              <node name="system">
+                <properties>
+                  <help>System parameters</help>
+                </properties>
+                <children>
+                  <leafNode name="conntrack">
+                    <properties>
+                      <help>Connection Tracking</help>
+                      <valueless/>
+                    </properties>
+                  </leafNode>
+                  <leafNode name="flow-accounting">
+                    <properties>
+                      <help>Flow accounting</help>
+                      <valueless/>
+                    </properties>
+                  </leafNode>
+                  <leafNode name="option">
+                    <properties>
+                      <help>System Options</help>
+                      <valueless/>
+                    </properties>
+                  </leafNode>
+                  <leafNode name="sflow">
+                    <properties>
+                      <help>sFlow</help>
+                      <valueless/>
+                    </properties>
+                  </leafNode>
+                  <leafNode name="static-host-mapping">
+                    <properties>
+                      <help>Map host names to addresses</help>
+                      <valueless/>
+                    </properties>
+                  </leafNode>
+                  <leafNode name="sysctl">
+                    <properties>
+                      <help>Configure kernel parameters at runtime</help>
+                      <valueless/>
+                    </properties>
+                  </leafNode>
+                </children>
+              </node>
               <leafNode name="vpn">
                 <properties>
                   <help>Virtual Private Network (VPN)</help>