Remove `MRB_TT_HAS_BASIC` macro
The value of `MRB_TT_HAS_BASIC` is meaningless because `MRB_TT_HAS_BASIC` is
no longer used with `MRB_WORD_BOXING` at
@@ -166,10 +166,8 @@ typedef void mrb_value;
#include "boxing_no.h"
#endif
-#define MRB_TT_HAS_BASIC MRB_TT_FREE
-
#ifndef mrb_immediate_p
-#define mrb_immediate_p(o) (mrb_type(o) < MRB_TT_HAS_BASIC)
+#define mrb_immediate_p(o) (mrb_type(o) < MRB_TT_FREE)
#endif
#ifndef mrb_fixnum_p
#define mrb_fixnum_p(o) (mrb_type(o) == MRB_TT_FIXNUM)
