writer/hlsl: Use the WrapArraysInStructs transform

Fixes issues with using arrays as function return types.

Fixed: tint:848
Change-Id: Iee8af0f2cea9d19e448176446c6599be2bd32316
Reviewed-on: https://dawn-review.googlesource.com/c/tint/+/54321
Kokoro: Kokoro <noreply+kokoro@google.com>
Reviewed-by: James Price <jrprice@google.com>

src/transform/hlsl.cc

@@ -25,6 +25,7 @@
 #include "src/transform/manager.h"
 #include "src/transform/promote_initializers_to_const_var.h"
 #include "src/transform/simplify.h"
+#include "src/transform/wrap_arrays_in_structs.h"
 
 namespace tint {
 namespace transform {
@@ -50,6 +51,7 @@ Output Hlsl::Run(const Program* in, const DataMap&) {
   manager.Add<CalculateArrayLength>();
   manager.Add<ExternalTextureTransform>();
   manager.Add<PromoteInitializersToConstVar>();
+  manager.Add<WrapArraysInStructs>();
   data.Add<CanonicalizeEntryPointIO::Config>(
       CanonicalizeEntryPointIO::BuiltinStyle::kStructMember);
   auto out = manager.Run(in, data);