ovs-ctl.in: Don't save kernel datapath config.

Commit a41754333f6 (ovs-ctl.in: Ability to save flows and kernel
datapath config.) made ovs-ctl able to usefully save and restore
the flow table across loading and unloading the OVS kernel module
and stopping and starting the OVS daemons.  To ensure that the
flow table was still meaningful, it ensured that the datapath port
numbers were the same with the old and new versions of the kernel
module.

However, later commit e1b1d06afde (Separate OpenFlow port numbers
from datapath ones.) changed the OpenFlow implementation so that
keeping the same datapath port numbers no longer ensured that the
OpenFlow port numbers would be the same.  This caused a regression
in saving and restoring the flow table.  Although the flow table
was still saved and restored, it was no longer useful, since the
datapath port numbers might change.

This commit does not fix the regression, but it does drop the code
that saves and restores the port datapath numbers, since it is no
longer useful.  The following commit fixes the regression.

Signed-off-by: Gurucharan Shetty <gshetty@nicira.com>