HAL_ChibiOS: implement flash driver

libraries/AP_HAL_ChibiOS/AP_HAL_ChibiOS_Namespace.h

@@ -26,4 +26,5 @@ namespace ChibiOS {
     class SoftSigReader;
     class SoftSigReaderInt;
     class CANManager;
+    class Flash;
 }

libraries/AP_HAL_ChibiOS/AP_HAL_ChibiOS_Private.h

@@ -14,3 +14,4 @@
 #include "RCInput.h"
 #include "RCOutput.h"
 #include "I2CDevice.h"
+#include "Flash.h"

libraries/AP_HAL_ChibiOS/HAL_ChibiOS_Class.cpp

@@ -82,6 +82,7 @@ static Empty::RCOutput rcoutDriver;
 static ChibiOS::Scheduler schedulerInstance;
 static ChibiOS::Util utilInstance;
 static Empty::OpticalFlow opticalFlowDriver;
+static ChibiOS::Flash flashDriver;
 
 
 #if HAL_WITH_IO_MCU
@@ -110,6 +111,7 @@ HAL_ChibiOS::HAL_ChibiOS() :
         &schedulerInstance,
         &utilInstance,
         &opticalFlowDriver,
+        &flashDriver,
         nullptr
         )
 {}