Fix argument error when built with MRB_WITHOUT_FLOAT flag

Fixed inproper argument of mrb_fixnum_value() called in integral_div(),
when built with MRB_WITHOUT_FLOAT flag.
Co-authored-by: taiyoslime <t@iyosli.me>
Co-authored-by: n4o847 <22975590+n4o847@users.noreply.github.com>

src/numeric.c

@@ -158,7 +158,7 @@ integral_div(mrb_state *mrb, mrb_value xv)
   if (y == 0) {
     mrb_raise(mrb, E_RUNTIME_ERROR, "devided by zero");
   }
-  return mrb_fixnum_value(mrb, mrb_fixnum(xv) / y);
+  return mrb_fixnum_value(mrb_fixnum(xv) / y);
 #else
   mrb_float x, y;