ospf6d: Fix when an "export-list" or "filter-list out" is applied.

ospf6d: Fix when an "export-list" or "filter-list out" is applied.

When an "export-filter" or "filter-list out" was configured on an area the
filter was not applied to existing database.    The user would either have
to restart the neighboring router in the other area or issue a "clear ipv6
ospf6 interface" to cause the neighbor router to resend it's LSAs.   The
new filter would then be applied to these LSAs and permit or deny summary
LSAs from being added/removed from the database.  The code now applies the
filters to the existing database without user needing to take any action
to clear ospfv3 adjacencies.

The second part of the problem was if a rule changed the updated filter was
not applied.  The code has been modifed to now process the rule update and
reapply the filter.

Signed-off-by: Lynne Morrison <lynne@voltanet.io>