Turn WiFi off before suspend

This might help avoiding stability issues with WiFi.

sleepwalk

@@ -42,6 +42,8 @@ start_deep_sleep() {
         sleep 5 # Give some extra time for pending output data
 
         if [ can_suspend ]; then
+		WIFI_WAS_ON=$(nmcli r wifi)
+		nmcli r wifi off
                 echo mem > /sys/power/state 2>/dev/null
         fi
 
@@ -210,6 +212,11 @@ if [ "$1" == "start" ]; then
                                 break
                         fi
                 done
+
+		if [ "$WIFI_WAS_ON" = "enabled" ]; then
+			nmcli r wifi on
+		fi
+
                 wait_for_notifications
         done
 elif [ "$1" == "stop" ]; then