This change attempts to fix the following sequence for nodes with
OVS ports that also have routes defined:
- state.sls linux.network; system.reboot; state.sls linux.network;

If an OVS port also has a route defined, a route cfg file is
created in </etc/network/if.{down,up}.d/>, which is sourced after
system reboot before we (eventually) re-run `interface.sls`, leaving
the OVS port in UP state, so `ifup` would fail.

Signed-off-by: Alexandru Avadanii <Alexandru.Avadanii@enea.com>