[clang] [llvm] [KMSAN] Enable on PowerPC64 (PR #73611)

[Fangrui Song via cfe-commits]

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@@ -0,0 +1,149 @@
+; RUN: opt < %s -S -msan-kernel=1 -passes=msan 2>&1 | FileCheck %s
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MaskRay wrote:

`llvm/test/Instrumentation/MemorySanitizer/PowerPC/vararg-ppc64.ll` does not follow the convention. I think the new test should follow other tests which follow the convention.

https://github.com/llvm/llvm-project/pull/73611