[ADT][NFC] Remove unused parameter from DenseMap::InsertIntoBucketImpl (#108382)

Remove unused parameter `Key` from `InsertIntoBucketImpl`

Author: marcauberer

llvm/include/llvm/ADT/DenseMap.h

@@ -570,7 +570,7 @@ class DenseMapBase : public DebugEpochBase {
   template <typename KeyArg, typename... ValueArgs>
   BucketT *InsertIntoBucket(BucketT *TheBucket, KeyArg &&Key,
                             ValueArgs &&...Values) {
-    TheBucket = InsertIntoBucketImpl(Key, Key, TheBucket);
+    TheBucket = InsertIntoBucketImpl(Key, TheBucket);
 
     TheBucket->getFirst() = std::forward<KeyArg>(Key);
     ::new (&TheBucket->getSecond()) ValueT(std::forward<ValueArgs>(Values)...);
@@ -580,16 +580,15 @@ class DenseMapBase : public DebugEpochBase {
   template <typename LookupKeyT>
   BucketT *InsertIntoBucketWithLookup(BucketT *TheBucket, KeyT &&Key,
                                       ValueT &&Value, LookupKeyT &Lookup) {
-    TheBucket = InsertIntoBucketImpl(Key, Lookup, TheBucket);
+    TheBucket = InsertIntoBucketImpl(Lookup, TheBucket);
 
     TheBucket->getFirst() = std::move(Key);
     ::new (&TheBucket->getSecond()) ValueT(std::move(Value));
     return TheBucket;
   }
 
   template <typename LookupKeyT>
-  BucketT *InsertIntoBucketImpl(const KeyT &Key, const LookupKeyT &Lookup,
-                                BucketT *TheBucket) {
+  BucketT *InsertIntoBucketImpl(const LookupKeyT &Lookup, BucketT *TheBucket) {
     incrementEpoch();
 
     // If the load of the hash table is more than 3/4, or if fewer than 1/8 of