[llvm] [AArch64][SelectionDAG] Enable new partial reduction lowering by default (PR #143565)

[Sam Tebbs via llvm-commits]

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@@ -649,69 +774,93 @@ define <4 x i32> @udot_no_bin_op(<4 x i32> %acc, <16 x i8> %a){
 define <4 x i32> @udot_no_bin_op_in_loop(ptr %p){
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SamTebbs33 wrote:

These check statements look identical to me, so they could share a `CHECK` prefix.

https://github.com/llvm/llvm-project/pull/143565