bgpd: fix AS4_PATH attr flag check (BZ#676)

AS_PATH is a well-known, transitive path attribute and cannot be flagged
as "Partial". This is what commit
77a20b8af32c926176f8492a086d9e4ec670496b implemented, but it did not
account, that bgp_attr_aspath() is also used to process AS4_PATH, which
is an optional, transitive path attribute and as such may be flagged as
"Partial". This change justfies the test condition.
1 file changed