[llvm] Move the PowerPC/PPCMergeStringPool work to initializer (PR #77352)

[Stefan Pintilie via llvm-commits]

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@@ -1148,7 +1148,7 @@ entry:
 
 attributes #0 = { nounwind }
 
-; AIXDATA: .csect L..__ModuleStringPool[RO],2
+; AIXDATA: .csect L..__ModuleStringPool[RO],3
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stefanp-ibm wrote:

Alignment change for ModuleStringPool csect.

https://github.com/llvm/llvm-project/pull/77352