PID: fixed example build

libraries/PID/examples/pid/pid.pde

@@ -11,11 +11,10 @@
 #include <PID.h> // ArduPilot Mega RC Library
 
 #include <AP_HAL_AVR.h>
-#if CONFIG_APM_HARDWARE == APM_HARDWARE_APM2
+#include <AP_HAL_AVR_SITL.h>
-const AP_HAL::HAL& hal = AP_HAL_AVR_APM2;
+#include <AP_HAL_Empty.h>
-#else
+
-const AP_HAL::HAL& hal = AP_HAL_AVR_APM1;
+const AP_HAL::HAL& hal = AP_HAL_BOARD_DRIVER;
-#endif
 
 long radio_in;
 long radio_trim;