Fix memory allocation.

The BLEDeviceEvent enum doesn't have 3 but 4 elements:
See src/BLEPeripheral.h line 58 to 61.

Author: honnet

src/BLEPeripheral.h

@@ -173,7 +173,7 @@ class BLEPeripheral : public BLEDeviceEventListener,
 
     BLECentral                     _central;
     BLEPeripheralEventHandler      _eventHandlers[4];
-    BLEDeviceEventHandler          _deviceEvents[3];
+    BLEDeviceEventHandler          _deviceEvents[4];
 
     BLEEirData                     advertisementData[3];
     BLEEirData                     scanData;