Fix "fmt % thing" : fmt missing the %s

With this the Livestatus was simply not usable at all within a scheduler :|

Seen while investigating on shinken-solutions/shinken#1623

Author: gst

module/module.py

@@ -184,7 +184,7 @@ def init(self):
     # will be in another process, so we will be able to hack objects
     # if need)
     def hook_pre_scheduler_mod_start(self, sched):
-        logger.info("[Livestatus Broker] pre_scheduler_mod_start::" % str(sched.__dict__))
+        logger.info("[Livestatus Broker] pre_scheduler_mod_start: %s", sched.__dict__)
         self.rg.load_from_scheduler(sched)
 
     # In a scheduler we will have a filter of what we really want as a brok