Replace the malloc.h header with stdlib.h.

--- src-ILU/ilur/ilur.c.orig	Wed Nov 19 22:50:22 2014
+++ src-ILU/ilur/ilur.c	Wed Nov 19 22:50:57 2014
@@ -1,6 +1,6 @@
 #include <string.h>
 #include <stdio.h>
-#include <malloc.h>
+#include <stdlib.h>
 
 #include <IL/il.h>
 #include <IL/ilu.h>
