[clang] [PowerPC] Disable float128 on AIX in Clang (PR #67298)

[Kai Luo via cfe-commits]

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@@ -52,7 +52,7 @@ bool PPCTargetInfo::handleTargetFeatures(std::vector<std::string> &Features,
       HasDirectMove = true;
     } else if (Feature == "+htm") {
       HasHTM = true;
-    } else if (Feature == "+float128") {
+    } else if (Feature == "+float128" && !getTriple().isOSAIX()) {
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bzEq wrote:

```suggestion
HasFloat128 = !getTriple().isOSAIX();
```

https://github.com/llvm/llvm-project/pull/67298