[llvm] [AArch64] Refactor @plt, @gotpcrel, and @AUTH to use parseDataExpr (PR #134202)

[Fangrui Song via llvm-commits]

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@@ -670,8 +670,6 @@ class AsmParser : public MCAsmParser {
   bool parseEscapedString(std::string &Data) override;
   bool parseAngleBracketString(std::string &Data) override;
 
-  const MCExpr *applySpecifier(const MCExpr *E, uint32_t Variant);
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MaskRay wrote:

Yes. AArch64AsmParser has access to `MCAsmParser` (base class) but not `AsmParser` (subclass, not exposed in a public header). This function has to be moved to be accessed by `MCAsmParser::parseAtSpecifier`, which is now called by AArch64AsmParser

https://github.com/llvm/llvm-project/pull/134202