[OpenACC] Add missing 'check' line to update-construct-ast test.

I must have deleted this by accident, and my local run's address managed
to have a '1' in the address, so it didn't catch it!  This corrects the
test.

Author: erichkeane

clang/test/SemaOpenACC/update-construct-ast.cpp

@@ -253,6 +253,7 @@ void TemplFunc(T t) {
   // CHECK-NEXT: ArraySectionExpr
   // CHECK-NEXT: ImplicitCastExpr
   // CHECK-NEXT: DeclRefExpr{{.*}} 'LocalArray' 'decltype(SomeStruct::value)[5]'
+  // CHECK-NEXT: IntegerLiteral{{.*}}0
   // CHECK-NEXT: IntegerLiteral{{.*}}1
 }