[llvm] [AArch64] Use SVE for load-extend-broadcast on V3AE (PR #221689)

[Benjamin Maxwell via llvm-commits]

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@@ -30209,7 +30117,8 @@ static SDValue performSelectCombine(SDNode *N,
 }
 
 static SDValue performDUPCombine(SDNode *N,
-                                 TargetLowering::DAGCombinerInfo &DCI) {
+                                 TargetLowering::DAGCombinerInfo &DCI,
+                                 const AArch64Subtarget *SubTarget) {
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MacDue wrote:

nit: `SubTarget` -> `Subtarget` (we don't typically capitalize "Target") 

https://github.com/llvm/llvm-project/pull/221689