rootfs: change start number of vlan.sh and enable_switching.sh

--vlan.sh needs RTU to be up. vlan.sh can be started at the same time as HAL,
  because wrs_vlans will wait for RTU.
--Postpone the start of enable_switching.sh to leave some numbers empty for
  other programs in the future.
--snmpd and lighttpd.sh can be started at the same time
Signed-off-by: Adam Wujek <adam.wujek@cern.ch>