Fix typo in flushing stats CF (#11055)

Summary: Pull Request resolved: https://github.com/facebook/rocksdb/pull/11055

Test Plan: make check

Reviewed By: cbi42

Differential Revision: D42232828

Pulled By: ajkr

fbshipit-source-id: 3b46514aebff4da7e47b9954b90800ba4a3ba30b

db/db_impl/db_impl_compaction_flush.cc

@@ -2200,7 +2200,7 @@ Status DBImpl::FlushMemTable(ColumnFamilyData* cfd,
             FlushRequest req{{cfd_stats, flush_memtable_id}};
             flush_reqs.emplace_back(std::move(req));
             memtable_ids_to_wait.emplace_back(
-                cfd->imm()->GetLatestMemTableID());
+                cfd_stats->imm()->GetLatestMemTableID());
           }
         }
       }