use same shell setup as in nix home manager

roles/pi_standard_setup/files/raspi-leds-off.sh

@@ -1,7 +1,11 @@
 #!/bin/bash
 
-echo none > /sys/class/leds/led0/trigger
-echo none > /sys/class/leds/led1/trigger
+for led in led0 led1 ACT PWR; do
+  path="/sys/class/leds/$led"
+  if [ -d "$path" ]; then
+    echo none > "$path/trigger" 2>/dev/null
+    echo 0 > "$path/brightness" 2>/dev/null
+  fi
+done
 
-echo 0 >/sys/class/leds/led0/brightness
-echo 0 >/sys/class/leds/led1/brightness
+exit 0