Only log room_modify event if some param was changed

vroom.pl

@@ -453,11 +453,11 @@ helper modify_room => sub {
   }
   if ($mods ne ''){
     $msg .= "\nModified fields:\n$mods";
-  }
     $self->log_event({
       event => 'room_modify',
       msg   => $msg
     });
+  }
   return 1;
 };