fix chnroute migrate

ansible/migrate-chnroute.yaml

@@ -24,7 +24,8 @@
     - name: chnroute
       become: true
       shell: |
-        ipset restore -f {{ansible_user_dir}}/nextgen-network/ipsets/chnrouter.ipset || true
+        ipset flush chnrouter
+        sed '/^create chnrouter hash:net family inet$/d' {{ansible_user_dir}}/nextgen-network/ipsets/chnrouter.ipset | ipset restore
     - name: reload_switch_rules
       become: true
       shell: '{{ansible_user_dir}}/nextgen-network/scripts/switch-rules-down.sh ; {{ansible_user_dir}}/nextgen-network/scripts/switch-rules-up.sh'