eliminate extra root id list placement in key nodes

src/hash_store/hash_store.c

@@ -345,8 +345,6 @@ hs_submit_data(HS_Key key, Arena **data_arena, String8 data)
               chunk->v = push_array_no_zero(n->arena, HS_ID, chunk->cap);
             }
             chunk->v[chunk->count] = key.id;
-            key_node->root_id_chunk_node = chunk;
-            key_node->root_id_chunk_idx = chunk->count;
             chunk->count += 1;
             n->ids.total_count += 1;
             break;

src/hash_store/hash_store.h

@@ -109,8 +109,6 @@ struct HS_KeyNode
 {
   HS_KeyNode *next;
   HS_KeyNode *prev;
-  HS_RootIDChunkNode *root_id_chunk_node;
-  U64 root_id_chunk_idx;
   HS_Key key;
   U128 hash_history[HS_KEY_HASH_HISTORY_COUNT];
   U64 hash_history_gen;