[clang] [llvm] [SCCP] Infer return attributes in SCCP as well (PR #106732)

[Yingwei Zheng via cfe-commits]

================
@@ -277,34 +277,12 @@ static bool runIPSCCP(
   // whether other functions are optimizable.
   SmallVector<ReturnInst*, 8> ReturnsToZap;
 
+  Solver.inferReturnAttributes();
   for (const auto &I : Solver.getTrackedRetVals()) {
     Function *F = I.first;
     const ValueLatticeElement &ReturnValue = I.second;
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dtcxzyw wrote:

```suggestion
  for (const auto &[F, ReturnValue] : Solver.getTrackedRetVals()) {
```

https://github.com/llvm/llvm-project/pull/106732