[clang] [Clang][AArch64] Add missing SME functions to header file. (PR #75791)

[Paul Walker via cfe-commits]

================
@@ -10570,6 +10570,26 @@ Value *CodeGenFunction::EmitAArch64BuiltinExpr(unsigned BuiltinID,
     return Builder.CreateCall(F, llvm::ConstantInt::get(Int32Ty, HintID));
   }
 
+  if (BuiltinID == clang::AArch64::BI__builtin_arm_get_sme_state) {
+    // Create call to __arm_sme_state and store the results to the two pointers.
----------------
paulwalker-arm wrote:

Out of interest why does this builtin return the result via memory? instead of being an alias of `__arm_sme_state`. Or rather, can `__arm_has_sme` and `__arm_in_streaming_mode` call `__arm_sme_state` directly?

https://github.com/llvm/llvm-project/pull/75791