[llvm] [LV] Remove DataAndControlFlowWithoutRuntimeCheck. NFC (PR #183762)

[David Sherwood via llvm-commits]

================
@@ -1327,11 +1324,10 @@ class LoopVectorizationCostModel {
   }
 
   /// Returns the TailFoldingStyle that is best for the current loop.
-  TailFoldingStyle getTailFoldingStyle(bool IVUpdateMayOverflow = true) const {
+  TailFoldingStyle getTailFoldingStyle() const {
     if (!ChosenTailFoldingStyle)
       return TailFoldingStyle::None;
-    return IVUpdateMayOverflow ? ChosenTailFoldingStyle->first
-                               : ChosenTailFoldingStyle->second;
+    return *ChosenTailFoldingStyle;
----------------
david-arm wrote:

nit: Can this just be a one-liner, i.e.

```
  return ChosenTailFoldingStyle ? *ChosenTailFoldingStyle : TailFoldingStyle::None;
```

In fact, do we still need `ChosenTailFoldingStyle` to be optional?

https://github.com/llvm/llvm-project/pull/183762