[clang] [clang][SYCL] Handle cdecl variadic functions for SYCL device (PR #194922)

[Mariya Podchishchaeva via cfe-commits]

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@@ -9752,7 +9752,7 @@ def warn_kern_is_inline : Warning<
   "ignored 'inline' attribute on kernel function %0">,
   InGroup<CudaCompat>;
 def err_variadic_device_fn : Error<
-  "CUDA device code does not support variadic functions">;
+  "%select{CUDA|SYCL}0 device code does not support variadic functions">;
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Fznamznon wrote:

I was surprised as well, I was hesitant to remove CUDA from it though in case some of downstreams use it.

https://github.com/llvm/llvm-project/pull/194922