selftests: openvswitch: adjust datapath NL message declaration

selftests: openvswitch: adjust datapath NL message declaration

The netlink message for creating a new datapath takes an array
of ports for the PID creation.  This shouldn't cause much issue
but correct it for future cases where we need to do decode of
datapath information that could include the per-cpu PID map.

Fixes: 25f16c873fb1 ("selftests: add openvswitch selftest suite")
Signed-off-by: Aaron Conole <aconole@redhat.com>
Link: https://lore.kernel.org/r/20230412115828.3991806-1-aconole@redhat.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>