[llvm] [NFC][SPIRV] Make the zero-length-array.ll test explicit about what is generated (PR #166910)

[Marcos Maronas via llvm-commits]

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@@ -1,10 +1,17 @@
 ; RUN: llc -verify-machineinstrs -O0 -mtriple=spirv-unknown-vulkan-compute %s -o - | FileCheck %s
 ; RUN: %if spirv-tools %{ llc -O0 -mtriple=spirv-unknown-vulkan-compute %s -o - -filetype=obj | spirv-val %}
 
-; CHECK: %[[#type:]] = OpTypeInt 32 0
-; CHECK: %[[#ext:]] = OpConstant %[[#type]] 0
+; Nothing is generated, but compilation doesn't crash
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maarquitos14 wrote:

```suggestion
; Nothing is generated, but compilation doesn't crash.
```

https://github.com/llvm/llvm-project/pull/166910