Update WARNING EXPERIMENTAL quant instructions

README.md

@@ -142,6 +142,7 @@ numactl -N 1 -m 1 \
 $ git clone https://github.com/ikawrakow/ik_llama.cpp
 $ cd ik_llama.cpp
 $ git remote add Thireus https://github.com/Thireus/ik_llama.cpp.git
+$ git fetch Thireus
 $ git checkout glm-4.5-clean
 
 # Build for hybrid CPU+CUDA