[llvm] [SPIR-V] Fix vloadn OpenCL builtin lowering (PR #81148)

[Nathan Gauër via llvm-commits]

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@@ -0,0 +1,40 @@
+; RUN: llc -O0 -mtriple=spirv64-unknown-unknown %s -o - | FileCheck %s
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Keenuts wrote:

nit: why not running spirv-val on this too?

https://github.com/llvm/llvm-project/pull/81148