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

[Kamau Bridgeman via cfe-commits]

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@@ -0,0 +1,80 @@
+#ifndef PPC_FEATURE
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kamaub wrote:

Missing file description similar to the `head` of `clang/include/clang/Basic/Builtins.def`

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