adds ehrenberg platform

libwrap/sys/sbrk.c

@@ -10,7 +10,7 @@ void *__wrap_sbrk(ptrdiff_t incr)
   static char *curbrk = _end;
 
   if ((curbrk + incr < _end) || (curbrk + incr > _heap_end))
-    return NULL - 1;
+    return (void*)- 1;
 
   curbrk += incr;
   return curbrk - incr;