count statistics in netmgr UDP code

- also restored a test in the statistics test which was changed when
  the netmgr was introduced because active sockets were not being
  counted.

bin/tests/system/statistics/tests.sh

@@ -71,7 +71,7 @@ $RNDCCMD -s 10.53.0.3 stats > /dev/null 2>&1
 [ -f ns3/named.stats ] || ret=1
 if [ ! "$CYGWIN" ]; then
     nsock0nstat=`grep "UDP/IPv4 sockets active" ns3/named.stats | awk '{print $1}'`
-    [ 0 -eq ${nsock0nstat:-0} ] || ret=1
+    [ 0 -ne ${nsock0nstat:-0} ] || ret=1
 fi
 if [ $ret != 0 ]; then echo_i "failed"; fi
 status=`expr $status + $ret`