minor : add TODO [no ci]

Author: ggerganov

src/llama-model.cpp

@@ -19860,6 +19860,7 @@ ggml_cgraph * llama_model::build_graph(const llm_graph_params & params) const {
     // if the gguf model was converted with --sentence-transformers-dense-modules
     // there will be two additional dense projection layers
     // dense linear projections are applied after pooling
+    // TODO: move reranking logic here and generalize
     llm->build_dense_out(dense_2_out_layers, dense_3_out_layers);
 
     return llm->res->get_gf();