torque: Fix AccessCheckInfo definition

AccessCheckInfo is a struct which is initialized with undefined values
as placeholders. Update the definiton so that the verifier that could
run between allocation and setting a field is happy.

Bug: chromium:967433
Change-Id: I21b99645c01e109d7ba0b61a5366e1f66a7f98d5
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1634922Reviewed-by: Jakob Gruber <jgruber@chromium.org>
Commit-Queue: Michael Lippautz <mlippautz@chromium.org>
Cr-Commit-Position: refs/heads/master@{#61918}

src/builtins/base.tq

@@ -782,9 +782,9 @@ extern class InterceptorInfo extends Struct {
 }
 
 extern class AccessCheckInfo extends Struct {
-  callback: Foreign | Zero;
-  named_interceptor: InterceptorInfo | Zero;
-  indexed_interceptor: InterceptorInfo | Zero;
+  callback: Foreign | Zero | Undefined;
+  named_interceptor: InterceptorInfo | Zero | Undefined;
+  indexed_interceptor: InterceptorInfo | Zero | Undefined;
   data: Object;
 }