[clang] [clang][SYCL] Implement address space attributes for SYCL (PR #200849)

[Tom Honermann via cfe-commits]

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@@ -0,0 +1,388 @@
+// RUN: %clang_cc1 -fsycl-is-host -fsyntax-only -std=c++20 -verify %s
+// RUN: %clang_cc1 -fsycl-is-device -fsyntax-only -std=c++20 -verify %s
+
+// The SYCL address space attributes are type attributes that may only appear on
+// the object type of an object pointer or object reference type. This test
+// exercises that appropriate diagnostics are issued for other uses.
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tahonermann wrote:

```suggestion
// The SYCL address space attributes are type attributes that may be applied
// to non-function non-reference types. This test exercises that appropriate
// diagnostics are issued for other uses.
```

https://github.com/llvm/llvm-project/pull/200849