[llvm] [IR] NFC: Remove 'experimental' from partial.reduce.add intrinsic (PR #158637)

[Matt Arsenault via llvm-commits]

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@@ -0,0 +1,25 @@
+; RUN: opt -S < %s | FileCheck %s
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arsenm wrote:

Don't use opt here 

https://github.com/llvm/llvm-project/pull/158637