[clang] [Clang][AArch64] Change SME attributes for shared/new/preserved state. (PR #76971)

[via cfe-commits]

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@@ -6852,30 +6852,73 @@ without changing modes.
   }];
 }
 
-def ArmSmeSharedZADocs : Documentation {
+def ArmInDocs : Documentation {
   let Category = DocCatArmSmeAttributes;
   let Content = [{
-The ``__arm_shared_za`` keyword applies to prototyped function types and specifies
-that the function shares SME's matrix storage (ZA) with its caller.  This
-means that:
+The ``__arm_in`` keyword applies to prototyped function types and specifies
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rsandifo-arm wrote:

This is referring to S before it has been defined.

https://github.com/llvm/llvm-project/pull/76971