[libunwind] [libunwind] Call `__arm_za_disable` before entering EH (PR #160905)

[Oliver Hunt via cfe-commits]

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@@ -1971,6 +1975,32 @@ Registers_arm64::operator=(const Registers_arm64 &other) {
   return *this;
 }
 
+void Registers_arm64::jumpto() {
+#if !defined(__APPLE__)
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ojhunt wrote:

I think better would be gating on a feature specific flag - it makes it easier to understand whether something is written the way it because the feature is not supported, or because the _implementation_ of that feature is different - in essence someone new comes along and says "there's an 'if !<vendor>', does the mean it is not available, or the abi is different?"

https://github.com/llvm/llvm-project/pull/160905