[llvm] [llvm] Use llvm::sort (NFC) (PR #96434)

[Fangrui Song via llvm-commits]

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@@ -612,10 +612,9 @@ void PipelineSolver::populateReadyList(
   }
 
   if (UseCostHeur) {
-    std::sort(ReadyList.begin(), ReadyList.end(),
-              [](std::pair<int, int> A, std::pair<int, int> B) {
-                return A.second < B.second;
-              });
+    llvm::sort(ReadyList, [](std::pair<int, int> A, std::pair<int, int> B) {
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MaskRay wrote:

less_second

https://github.com/llvm/llvm-project/pull/96434