[clang] [PowerPC] Support local-dynamic TLS relocation on AIX (PR #66316)

[Amy Kwan via cfe-commits]

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@@ -1622,6 +1629,9 @@ def TLSGDAIX8 :
                      "#TLSGDAIX8",
                      [(set i64:$rD,
                        (PPCTlsgdAIX i64:$offset, i64:$handle))]>;
+// This pseudo is expanded to load module-handle in X3, and the call to GETtlsMOD64AIX.
----------------
amy-kwan wrote:

```suggestion
// This pseudo is expanded to load the module-handle in X3, and the call to GETtlsMOD64AIX.
```

https://github.com/llvm/llvm-project/pull/66316