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

[Sam Tebbs via llvm-commits]

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@@ -35,6 +35,11 @@ struct AArch64FunctionInfo;
 class AArch64Subtarget;
 class MachineInstr;
 
+struct TPIDR2Object {
+  unsigned FrameIndex = 0;
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SamTebbs33 wrote:

It looks safer to do what other code does as well, done.

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