Update readme for ckpt removal instructions

rocAL_pybind/examples/rocAL_training_example/README.md

@@ -5,6 +5,7 @@ This version has been modified to use rocAL. It assumes that the dataset is raw
 
 To run use the following command
 ```bash
+rm *.pth.tar # Remove older checkpoints saved in the folder if the example has been run before
 python3 main.py -a resnet50 --dist-url='tcp://127.0.0.1:4321' --dist-backend 'nccl' --multiprocessing-distributed --world-size 1 --rank 0 -j$(nproc) --batch-size 1024 --rocal-cpu --epochs 91 /media/imageNetCompleteDataset/
 ```