Write out object & command,ip l s=ip link set

Make prepare-suspend easier to read for those less familiar with the objects and commands available to `ip`.

qubes-rpc/prepare-suspend

@@ -32,7 +32,7 @@ if [ "$action" = "suspend" ]; then
         if [ "$(cat "/sys/class/net/$intf/device/devtype" 2>/dev/null$)" = "vif" ]; then
             continue
         fi
-        ip l s "$intf" down
+        ip link set "$intf" down
     done
 
     # detach all drivers from PCI devices (the real ones, not emulated by qemu)