ospf6d: remove duplicated log

ospf6d: remove duplicated log

When running topotest ospf6_topo2 we can see a log message with wrong lsa id

2021/12/20 23:14:40.330 OSPF6: [V8P0C-HB5Z2] ASBR[default:Status:3]: Update
2021/12/20 23:14:40.330 OSPF6: [Z489N-JAJ6P] ASBR[default:Status:3]: Already ASBR
2021/12/20 23:14:40.330 OSPF6: [Z9D0B-12SBJ] Redistribute 2001:db8:2::/64 (connected)
2021/12/20 23:14:40.330 OSPF6: [N66XP-ANN4G] Advertise as AS-External Id:8.70.41.177 prefix 2001:db8:2::/64 metric 2   (**)
2021/12/20 23:14:40.330 OSPF6: [K4Y9R-C22T6] Advertise new AS-External Id:0.0.0.3 prefix 2001:db8:2::/64 metric 2
2021/12/20 23:14:40.330 OSPF6: [PKX0N-KNRQR] Originate AS-External-LSA for 2001:db8:2::/64

This PR removes the log (instead of fixing it) as same information is printed
in the following entry

Signed-off-by: ckishimo <carles.kishimoto@gmail.com>