Add the code and set_code methods on code, in order to remove the
TYPE_CODE macro. In this patch, the TYPE_CODE macro is changed to use
type::code, so all the call sites that are used to set the type code are
changed to use type::set_code. The next patch will remove TYPE_CODE
completely.
gdb/ChangeLog:
* gdbtypes.h (struct type) <code, set_code>: New methods.
(TYPE_CODE): Use type::code. Change all call sites used to set
the code to use type::set_code instead.
67607e24d0