port: fix fda initialization.

Initialize all descriptors to prevent polling invalid descriptors from
faulty ports.

Signed-off-by: Miroslav Lichvar <mlichvar@redhat.com>
clock: keep ports in specified order.

When adding a new port, put it at the end of the list instead of head.
This restores the order of received management messages as was before
commit 08575133.

Signed-off-by: Miroslav Lichvar <mlichvar@redhat.com>