DataFlash: correct use of #defines

HIL_BOARD_AVR_SITL was renamed
Move use of define to after include where it is defined

libraries/DataFlash/DataFlash_MAVLink.cpp

@@ -527,7 +527,7 @@ bool DataFlash_MAVLink::send_log_block(struct dm_block &block)
     if (comm_get_txspace(chan) < 500) {
         return false;
     }
-#if CONFIG_HAL_BOARD == HAL_BOARD_AVR_SITL
+#if CONFIG_HAL_BOARD == HAL_BOARD_SITL
     if (rand() < 0.1) {
         return false;
     }

libraries/DataFlash/DataFlash_SITL.h

@@ -4,9 +4,10 @@
 #ifndef __DATAFLASH_SITL_H__
 #define __DATAFLASH_SITL_H__
 
+#include <AP_HAL/AP_HAL.h>
+
 #if CONFIG_HAL_BOARD == HAL_BOARD_SITL
 
-#include <AP_HAL/AP_HAL.h>
 #include "DataFlash_Block.h"
 
 class DataFlash_SITL : public DataFlash_Block