Make two octave_classdef member functions public (bug #45833).

* libinterp/octave-value/ov-classdef.h (octave_classdef::loadobj,
octave_classdef::saveobj): Change methods from private to public.

Author: Nithin Lakshmisha

libinterp/octave-value/ov-classdef.h

@@ -166,8 +166,6 @@ class octave_classdef : public octave_base_value
   static std::string static_class_name () { return "<unknown>"; }
   static OCTINTERP_API void register_type (octave::type_info&);
 
-private:
-
   // Load an array of the size dv using a vector with
   // * a map with the values of the class properties
   // * a unique identifier of the object in the file