[llvm] [RegisterCoalescer] Fix incorrect VNInfo deletion condition in pruneSubRegValues (PR #195023)

[Matt Arsenault via llvm-commits]

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@@ -0,0 +1,63 @@
+; RUN: llc -mtriple=riscv64 -O1 %s -o - | FileCheck %s
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arsenm wrote:

```suggestion
; RUN: llc -mtriple=riscv64 -O1 < %s | FileCheck %s
```

Remove the -O1. If it's necessary to reproduce, this probably needs an additional MIR test for stability 

https://github.com/llvm/llvm-project/pull/195023