libyang CHANGE headers includes cleanup using include-what-you-use tool (#1098)

diff --git a/tools/lint/linenoise/linenoise.h b/tools/lint/linenoise/linenoise.h
index c708990..2bebcf3 100644
--- a/tools/lint/linenoise/linenoise.h
+++ b/tools/lint/linenoise/linenoise.h
@@ -39,6 +39,8 @@
 #ifndef __LINENOISE_H
 #define __LINENOISE_H
 
+#include <stddef.h>
+
 #ifdef __cplusplus
 extern "C" {
 #endif