Use pgmspace.h of typical AVR

Author: giulcioffi

Diff for: cores/arduino/Arduino.h

@@ -20,9 +20,10 @@
 #ifndef Arduino_h
 #define Arduino_h
 
+#include "../../tools/pgmspace.h"
+
 #include "api/ArduinoAPI.h"
 
-#include <avr/pgmspace.h>
 #include <avr/io.h>
 #include <avr/interrupt.h>