[llvm] [clang] [PowerPC][X86] Make cpu id builtins target independent and lower for PPC (PR #68919)

[Amy Kwan via cfe-commits]

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@@ -32,6 +32,7 @@ class PPCTargetMachine final : public LLVMTargetMachine {
   std::unique_ptr<TargetLoweringObjectFile> TLOF;
   PPCABI TargetABI;
   Endian Endianness = Endian::NOT_DETECTED;
+  mutable bool HasGlibcHWCAPAccess = false;
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amy-kwan wrote:

Question: Why does this need to be mutable?

https://github.com/llvm/llvm-project/pull/68919