[llvm] [ARM][AArch64] autogenerate header file for TargetParser from Target tablegen files (PR #88378)

[Tomas Matheson via llvm-commits]

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@@ -144,7 +144,6 @@ void AArch64Subtarget::initializeProperties(bool HasMinSize) {
   case CortexA78C:
   case CortexR82:
   case CortexX1:
-  case CortexX1C:
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tmatheson-arm wrote:

For AArch64 specifically, there is no `SubtargetFeature` corresponding to `CortexX1C`, and therefore `ARMProcFamily` can never be set to this value. There were a few enum values like this that could never be set.

https://github.com/llvm/llvm-project/pull/88378