[llvm] [SPIR-V] Add capability for non-uniform indexing for `StructuredBuffer` types. (PR #163424)

[Nathan Gauër via llvm-commits]

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@@ -3,6 +3,7 @@
 
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Keenuts wrote:

But seems like we only have vulkan1.2 as minimum in the triple, so for now, never adding the extension is OK.

https://github.com/llvm/llvm-project/pull/163424