doxygen : Add include path in stdio.h
if not, we cannot know which header we should include for using 'puts' api
@@ -401,7 +401,8 @@ int ungetc(int c, FAR FILE *stream);
int printf(FAR const char *format, ...);
/**
* @brief put a string on standard output
- * @details POSIX API (refer to : http://pubs.opengroup.org/onlinepubs/9699919799/)
+ * @details @b #include <stdio.h> \n
+ * POSIX API (refer to : http://pubs.opengroup.org/onlinepubs/9699919799/)
* @since Tizen RT v1.0
*/
int puts(FAR const char *s);
