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

[Fangrui Song via cfe-commits]

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@@ -1360,6 +1372,9 @@ void XCOFFObjectWriter::assignAddressesAndIndices(const MCAsmLayout &Layout) {
 
   // Calculate indices for undefined symbols.
   for (auto &Csect : UndefinedCsects) {
+    // AIX does not need to emit for the _$TLSML symbol.
+    if (Csect.getSymbolTableName().equals(StringRef("_$TLSML")))
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MaskRay wrote:

`== "..."`

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