tree data BUGFIX do not require string value in dictionary

... when using them in any node values. It was not
documented and redundant.
diff --git a/src/tree_data_internal.h b/src/tree_data_internal.h
index 90de1f8..3cf45c6 100644
--- a/src/tree_data_internal.h
+++ b/src/tree_data_internal.h
@@ -270,7 +270,7 @@
  * @param[in] schema Schema node of the new data node.
  * @param[in] value Value of the any node.
  * @param[in] value_type Value type of the value.
- * @param[in] use_value Whether to directly assign (eat) the value or duplicate it.
+ * @param[in] use_value Whether to use dynamic @p value or duplicate it.
  * @param[out] node Created node.
  * @return LY_SUCCESS on success.
  * @return LY_ERR value if an error occurred.