YIN parser BUGFIX store parsed keyword id in extension substatements

TODO substatements still are not correctly parsed since their arguments
are stored as attribute substatements instead of getting them (for the
known statements) and storing them as the statement's argument value.
diff --git a/src/parser_yin.h b/src/parser_yin.h
index b4133af..c4c02b9 100644
--- a/src/parser_yin.h
+++ b/src/parser_yin.h
@@ -252,12 +252,14 @@
  * @param[in,out] ctx Yin parser context for logging and to store current state.
  * @param[in] name Name of element.
  * @param[in] name_len Length of elements Name.
+ * @param[in] name prefix of element.
+ * @param[in] name_len Length of elements prefix.
  * @param[in,out] data Data to read from, always moved to currently handled character.
  * @param[out] element Where the element structure should be stored.
  *
  * @return LY_ERR values.
  */
-LY_ERR yin_parse_element_generic(struct yin_parser_ctx *ctx, const char *name, size_t name_len, const char **data,
+LY_ERR yin_parse_element_generic(struct yin_parser_ctx *ctx, const char *name, size_t name_len, const char *prefix, size_t prefix_len, const char **data,
                                  struct lysp_stmt **element);
 
 /**