ospf6d: fix ospf6d crash during sigterm/shutdown

ospf6d: fix ospf6d crash during sigterm/shutdown

During signterm (shutdown) ospf6_clean calls route_remove
for brouter_table, during route_remove brouter_table remove
hook function is invoked which in turns calls router_remove
is any of the LSA has max age or cost is infinity,
which leads to stack corruption trying to delete same
route node.
Similar to 'no router ospf6' or 'no area ..' command
where lsdb is cleanedup then brouter route table
clean up is called.

Clean some of route trace to have route related fields.

Ticket:CM-17932

Signed-off-by: Chirag Shah <chirag@cumulusnetworks.com>