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

[Michal Paszkowski 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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michalpaszkowski wrote:

I added a comment below. It looks like the SPIR-V validator is doing additional checks on the arguments of those OpExtInst calls and those are not valid here. I want this test to only check the vloadn builtin name resolution to keep the tests as small as possible.
```
; This test only intends to check the vloadn builtin name resolution.
; The calls to the OpenCL builtins are not valid and will not pass SPIR-V validation.
```


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