include posix_memalign() declaration in dmmlib.h if needed

include/dmmlib/dmmlib.h

@@ -29,6 +29,7 @@
 
 #ifndef DMMLIB_H
 #define DMMLIB_H
+#include <dmmlib/config.h>
 #include <dmmlib/allocator.h>
 
 /** Global variable storing allocator's settings */
@@ -68,6 +69,10 @@ void * realloc(void *ptr, size_t size);
  */
 void * calloc(size_t count, size_t size);
 
+#ifdef WITH_MEMALIGN
+#include <dmmlib/memalign.h>
+#endif /* WITH_MEMALIGN */
+
 #endif /* ! STDLIB_H */
 
 #endif /* DMMLIB_H */