This adjustment of the locks fixes the race condition when a mwan3
hotplug script and a mwan3 command are running at the same time.
Signed-off-by: Florian Eckert <fe@dev.tdt.de>
User scripts conversion from luci-app-wan3 will be simplified if the variables
are passed by env instead of arguments.
Signed-off-by: Florian Eckert <fe@dev.tdt.de>