[clang] [CIR] Better handling of `void` function return (PR #128089)

[Andy Kaylor via cfe-commits]

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@@ -2,12 +2,12 @@
 // RUN: %clang_cc1 -std=c++20 -triple x86_64-unknown-linux-gnu -fclangir -emit-cir %s -o -  | FileCheck %s
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andykaylor wrote:

It's definitely unfortunate that we're adding this parsing code but don't have any tests for it. I'm working on a PR to bring cir-opt over so we can do that.

https://github.com/llvm/llvm-project/pull/128089