[llvm] [LV][NFC] Rename ScalarEpilogueLowering to EpilogueLowering (PR #191871)

[Florian Hahn via llvm-commits]

================
@@ -1310,16 +1310,16 @@ class LoopVectorizationCostModel {
     return false;
   }
 
-  /// Returns true if a scalar epilogue is allowed (e.g.., not prevented by
+  /// Returns true if an epilogue is allowed (e.g.., not prevented by
----------------
fhahn wrote:

nit: while you are touching this line
```suggestion
  /// Returns true if an epilogue is allowed (e.g., not prevented by
```

https://github.com/llvm/llvm-project/pull/191871