PR c/79022 fix mismatch parameter order in declaratio

PR c/79022 fix mismatch parameter order in declaratio

The declaration of create_nested_ptr_option in the header has the 'from'
and 'to' parameters in the opposite order from the definition in
gengtype.c:

  /* Return an options structure for a "nested_ptr" option.  */
  options_p
  create_nested_ptr_option (options_p next, type_p t,
                            const char *to, const char *from)

and the only caller in gengtype-parse.c:

  return create_nested_ptr_option (prev, ty, to, from);

This patch swaps the parameter names in the declaration.

	PR c/79022
	* gengtype.h (create_nested_ptr_option): Fix parameter names to match
	definition.

From-SVN: r269990