rewrite json_get_vars to jsonfilter

package/gluon-respondd/files/etc/hotplug.d/iface/10-gluon-respondd

@@ -1,22 +1,18 @@
 #!/bin/sh
 
-. /usr/share/libubox/jshn.sh
 . /lib/functions/service.sh
 
 DEVLIST=/var/run/gluon-respondd.devs
 
 ifname_to_dev () {
-  json_load "$(ubus call network.interface.$1 status)"
-  json_get_var dev device
-
-  echo "$dev"
+  ifstatus client "$1"|jsonfilter -e "@.device"
 }
 
 case "$ACTION" in
   ifup)   
     DEVICE="$(ifname_to_dev "$INTERFACE")"
 
-    [ "$DEVICE" == $(cat /lib/gluon/respondd/client.dev) ] && 
+    [ "$DEVICE" != "$(cat /lib/gluon/respondd/client.dev)" ] || 
       /etc/init.d/gluon-respondd restart_if_running &
     ;;
 esac