* command.c (add_set_cmd, no_just_help_class_command): Change

	* command.c (add_set_cmd, no_just_help_class_command): Change
	to make this the sfunc, not cfunc, since that is how we call it.
	* command.h: Comment difference between sfunc and cfunc.
	* demangle.c (set_demangling_command): Add third arg since that
	is how it is called.
	(_initialize_demangler): Use sfunc, not cfunc, for
	set_demangling_command, since that is how it is called.
	Remove show_demangling_command; it has no effect.