libyang REFACTOR config.h code split

... into compat.h and version.h.
diff --git a/src/validation.c b/src/validation.c
index 7ee6fdb..b5e86d9 100644
--- a/src/validation.c
+++ b/src/validation.c
@@ -19,8 +19,8 @@
 #include <stdlib.h>
 #include <string.h>
 
+#include "compat.h"
 #include "common.h"
-#include "config.h"
 #include "diff.h"
 #include "hash_table.h"
 #include "log.h"