Move update of the final optional ODE total frame stat inside the OdeLock rather than outside to avoid a very occasional race condition with the stat collection thread

OpenSim/Region/Physics/OdePlugin/OdeScene.cs

@@ -3227,10 +3227,10 @@ namespace OpenSim.Region.Physics.OdePlugin
                 }
 
                 tickCountFrameRun = Util.EnvironmentTickCount();
-            }
 
                 if (CollectStats)
                     m_stats[ODETotalFrameMsStatName] += Util.EnvironmentTickCountSubtract(startFrameTick);
+            }
 
             return fps;
         }