[clang] [llvm] [llvm][AArch64] Support -mcpu=apple-m4 (PR #95478)

[Jon Roelofs via cfe-commits]

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@@ -1010,6 +1034,9 @@ def : ProcessorModel<"apple-a16", CycloneModel, ProcessorFeatures.AppleA16,
                      [TuneAppleA16]>;
 def : ProcessorModel<"apple-a17", CycloneModel, ProcessorFeatures.AppleA17,
                      [TuneAppleA17]>;
+def : ProcessorModel<"apple-m4", CycloneModel, ProcessorFeatures.AppleM4,
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jroelofs wrote:

We should probably rearrange them to remove that distinction though, so that aliases that share the same `ProcessorFeatures.AppleA*` are together. I'll do that in a follow-up commit.

https://github.com/llvm/llvm-project/pull/95478