Remove unused is_recursive entry

This only takes up space and time.

UPGRADING.INTERNALS

@@ -118,6 +118,7 @@ PHP 8.3 INTERNALS UPGRADE NOTES
  e. ext/spl
    - The PHPAPI spl_iterator_apply() function now returns zend_result instead of int.
      There are no functional changes.
+   - The field _spl_filesystem_object->is_recursive has been removed.
 
  f. ext/dom
    - A new function dom_get_doc_props_read_only() is added to gather the document

ext/spl/spl_directory.c

@@ -759,8 +759,6 @@ static void spl_filesystem_object_construct(INTERNAL_FUNCTION_PARAMETERS, zend_l
 
 	}
 	zend_restore_error_handling(&error_handling);
-
-	intern->u.dir.is_recursive = instanceof_function(intern->std.ce, spl_ce_RecursiveDirectoryIterator) ? 1 : 0;
 }
 /* }}} */
 

ext/spl/spl_directory.h

@@ -64,7 +64,6 @@ struct _spl_filesystem_object {
 			php_stream         *dirp;
 			zend_string        *sub_path;
 			int                index;
-			int                is_recursive;
 			zend_function      *func_rewind;
 			zend_function      *func_next;
 			zend_function      *func_valid;