[clang] [clang][SYCL] Add SYCL spelling for AS attributes (PR #200849)

[Tom Honermann via cfe-commits]

================
@@ -42,6 +42,8 @@ static const unsigned NVPTXAddrSpaceMap[] = {
     1, // sycl_global_host
     3, // sycl_local
     0, // sycl_private
+    0, // sycl_generic
+    0, // sycl_constant
----------------
tahonermann wrote:

I think `sycl_constant` should match `opencl_constant` and `cuda_constant` here.

```suggestion
    4, // sycl_constant
```

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