Fixed digitalPinToPort and digitalPinToBitMask macros. (thanks to alvesjc)

Author: cmaglie

hardware/arduino/sam/cores/arduino/Arduino.h

@@ -54,8 +54,8 @@ extern void loop( void ) ;
 // Get the bit location within the hardware port of the given virtual pin.
 // This comes from the pins_*.c file for the active board configuration.
 //
-#define digitalPinToPort(P)        ( g_APinDescription[P]->pPort )
-#define digitalPinToBitMask(P)     ( g_APinDescription[P]->ulPin )
+#define digitalPinToPort(P)        ( g_APinDescription[P].pPort )
+#define digitalPinToBitMask(P)     ( g_APinDescription[P].ulPin )
 #define digitalPinToTimer(P)       (  )
 //#define analogInPinToBit(P)        ( )
 #define portOutputRegister(port)   ( port->PIO_ODSR )