watchdog: Make unbound a conditional service

If unbound is not installed or is disabled, don't even examine it if
it's running.

watchdog/watchdog.sh

@@ -28,8 +28,8 @@
 set -ex
 
 # Configuration
-COND_SERVICES="nethist lcollect"
-SERVICES="ucollect unbound"
+COND_SERVICES="nethist lcollect unbound"
+SERVICES="ucollect"
 for S in $COND_SERVICES ; do
 	if test -x "/etc/init.d/$S" && "/etc/init.d/$S" enabled ; then
 		SERVICES="$SERVICES $S"