Disable mmap on s390x in llama-quant too

Author: AlekseiNikiforovIBM

src/llama-quant.cpp

@@ -514,7 +514,7 @@ static void llama_model_quantize_impl(const std::string & fname_inp, const std::
 
     // mmap consistently increases speed Linux, and also increases speed on Windows with
     // hot cache. It may cause a slowdown on macOS, possibly related to free memory.
-#if defined(__linux__) || defined(_WIN32)
+#if (defined(__linux__) && !defined(__s390x__)) || defined(_WIN32)
     constexpr bool use_mmap = true;
 #else
     constexpr bool use_mmap = false;