Stabilize NVIDIA GPU device mapping across loaders

iso/overlay/usr/local/bin/bee-john-gpu-stress

@@ -152,14 +152,19 @@ done
 
 [ -n "${FINAL}" ] || { echo "no NVIDIA GPUs selected after filters" >&2; exit 1; }
 
+export CUDA_DEVICE_ORDER="PCI_BUS_ID"
+export CUDA_VISIBLE_DEVICES="${FINAL}"
+
 JOHN_DEVICES=""
+local_id=1
 for id in $(echo "${FINAL}" | tr ',' ' '); do
-    opencl_id=$((id + 1))
+    opencl_id="${local_id}"
     if [ -z "${JOHN_DEVICES}" ]; then
         JOHN_DEVICES="${opencl_id}"
     else
         JOHN_DEVICES="${JOHN_DEVICES},${opencl_id}"
     fi
+    local_id=$((local_id + 1))
 done
 
 echo "loader=john"