Move header includes before extern c (#1047)

include/portable.h

@@ -94,14 +94,14 @@
     #define configSTACK_ALLOCATION_FROM_SEPARATE_HEAP    0
 #endif
 
+#include "mpu_wrappers.h"
+
 /* *INDENT-OFF* */
 #ifdef __cplusplus
     extern "C" {
 #endif
 /* *INDENT-ON* */
 
-#include "mpu_wrappers.h"
-
 /*
  * Setup the stack of a new task so it is ready to be placed under the
  * scheduler control.  The registers have to be placed on the stack in