[llvm] [AArch64][SME] Remove unused ZA lazy-save (PR #81648)

[Sander de Smalen via llvm-commits]

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@@ -35,6 +35,11 @@ struct AArch64FunctionInfo;
 class AArch64Subtarget;
 class MachineInstr;
 
+struct TPIDR2Object {
+  unsigned FrameIndex = std::numeric_limits<int>::max();
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sdesmalen-arm wrote:

```suggestion
  int FrameIndex = std::numeric_limits<int>::max();
```

Frame indices are always signed integers (negative frame indices are for pre-allocated objects, like stack arguments). Also, you're using `std::numeric_limits<int>`, so that also suggests to use `int` for the type.

https://github.com/llvm/llvm-project/pull/81648