Fix another inherited variable in base::newsyslog::messages::sa

The ::override subclass was also using the class variable.

manifests/newsyslog/messages/sa/override.pp

@@ -10,7 +10,7 @@ class base::newsyslog::messages::sa::override (
    Base::Newsyslog::Config["messages"] {
         frequency => "daily",
         directory => "/var/log",
-        restart   => "hup $messagesPIDFile",
+        restart   => "hup ${pid_file}",
         archive   => "/afs/ir/service/clients/$clientdir/logs",
         log_owner => "root",
         log_group => $group,
@@ -19,4 +19,4 @@ class base::newsyslog::messages::sa::override (
         analyze   => "/usr/bin/filter-syslog",
         save_num  => $save_num,
    }
-}
\ No newline at end of file
+}