bgpd: Delete AS_CONFED_SEQUENCE when prepending an AS_SEQUENCE type segment

AS_CONFED_SEQUENCE segment should always be deleted when prepending
(e.g. with a route-map) an AS_SEQUENCE segment to an AS path. Otherwise,
AS_CONFED_SEQUENCE will not be deleted later when updating EBGP peers (since
it is not the leftmost segment) and will leak outside the confederation.
1 file changed