buildroot

package/netplug: init script create needed lock directory

Init script use /var/lock/subsys/netplugd but directory
/var/lock/subsys can be missing.

Signed-off-by: Julien Corjon <corjon.j@ecagroup.com>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
(cherry picked from commit c81c6d8f3d5bdf1825acaa27428c9e25def48593)
Signed-off-by: Peter Korsgaard <peter@korsgaard.com>