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

[via cfe-commits]

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@@ -3696,6 +3696,12 @@ def err_sme_definition_using_sm_in_non_sme_target : Error<
   "function executed in streaming-SVE mode requires 'sme'">;
 def err_sme_definition_using_za_in_non_sme_target : Error<
   "function using ZA state requires 'sme'">;
+def err_conflicting_attributes_sme_state : Error<
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rsandifo-arm wrote:

`arm_state` might be better than `sme_state` (as for the errors below).  The new keywords aren't in principle specific to SME.

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