OSA and bridge_role=primary on boot

Hello,
I am using debian stretch and I am trying to have openvswitch to work right
after rebooting the machine.

So far, I manually configure the card with znetconf and then start
openvswitch and then manually bring up the interfaces.

To visualize my approach, I list the commands (bridge and port had already
been added to ovs beforehand):
# znetconf -a [ccwdev0] -o layer2=1 -o bridge_role=primary
# systemctl start openvswitch-switch
# ip l s [ccwdev0] up
# ip l s br0 up

Everything works out fine, I can now live migrate vm's via virsh.

What options do I have to add to
/etc/sysconfig/hardware/config-ccw-0.0.[ccwdev0] to set the bridge_role
when the interface is brought up?

Best,
Benjamin.