[clang] [llvm] [SPIR-V] Fixup storage class for global private (PR #116636)

[Nathan Gauër via cfe-commits]

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@@ -58,6 +58,7 @@ enum class LangAS : unsigned {
 
   // HLSL specific address spaces.
   hlsl_groupshared,
+  hlsl_private,
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Keenuts wrote:

We hoped to split the PRs between back-end and FE, shall I land both at the same time?

https://github.com/llvm/llvm-project/pull/116636