Fix the metric name used for InnoDB mutex locks.

The metric name ought to be `mysql.innodb.locks'.

Change-Id: I7297ab0822fc945d60fde5b8be849155b74557cd

collectors/0/mysql.py

@@ -256,7 +256,7 @@ def printmetric(metric, value, tags=""):
       wait_count = int(status.split("=", 1)[1])
       waits[mutex] = waits.get(mutex, 0) + wait_count
     for mutex, wait_count in waits.iteritems():
-      printmetric(mutex, wait_count)
+      printmetric("innodb.locks", wait_count, " mutex=" + mutex)
 
   slave_status = todict(db, db.query("SHOW SLAVE STATUS")[0])
   master_host = slave_status["master_host"]