roles/named: Send application logs to syslog

BIND sends its normal application logs (as opposed to query logs) to the
`default_debug` channel.  By sending these log messages to syslog, they
can be routed and rotated using the normal system policies.  Using a
separate dedicated log file just ends up consuming a lot of space, as it
is not managed by any policy.

roles/named/templates/named.conf.j2

@@ -74,7 +74,7 @@ options {
 
 logging {
 	channel default_debug {
-                file "data/named.run";
+		syslog daemon;
 		severity dynamic;
 	};
 {% if named_queries_syslog %}