BGP on BSD was bound to random port. I am surprised that
nobody noticed it already.

To be consistent with other daemons.

Although standard says that if we receive AS_PATH_CONFED_*
(and we are not a part of a confederation) segment, we should
drop session, nobody does that and it is unwise to do that.

Now we drop session just in case that peer ASN is in
AS_PATH_CONFED_* segment (to detect peer that considers BIRD
as a part of its confederation).

If other side of a socket is sending data faster than
BIRD is processing, BIRD does not schedule any other
callbacks (events, timers, rx/tx callbacks).

Also does some reorganization in RT LSA announcement.

The difference is here to reject incoming connections in the
first case.

only for name, never for value in function filter_same()