Fix STM32 compatibility

Remove workarounf for va_start and va_end not defined

See:
stm32duino/Arduino_Core_STM32#240

Fix:
stm32duino/Arduino_Core_STM32#253

Signed-off-by: Frederic Pillon <[email protected]>

Author: fpistm

src/DebugUtil.cpp

@@ -1,17 +1,11 @@
 #include "DebugUtil.h"
+#include "wiring_private.h"
 
 #if defined(ARDUINO_ARCH_SAMD) || defined(ARDUINO_ARCH_STM32)
     extern "C" char* sbrk(int incr);
     extern char *__brkval;
 #endif
 
-//workaround for va_start & va_end for STM32
-#if defined(ARDUINO_ARCH_STM32)
-#include <stdarg.h>
-#define va_start(v,l)	__builtin_va_start(v,l)
-#define va_end(v)	__builtin_va_end(v)
-#endif
-
 // DebugUtil unique instance creation
 DebugUtil DebugUtil::Debug;
 DebugUtil& Debug = DebugUtil::Debug;