Update to 2.9.0
    
    2021-12-08 Jerry Lundström
    
        Release 2.9.0
    
        This release brings a new message suppression option and a way to control
        how many queries are sent over a connection.
    
        You can now suppress the message about receiving unexpected DNS message
        IDs by using `-O suppress=unexpected`.
    
        With `-O num-queries-per-conn=<num>` you can now limit the number of
        queries sent over a connection before triggering a re-connection, see
        the `dnsperf(3)` man-page for more information how this works.
    
        cd9df40 Tests
        864a968 Queries per connection
        7c5d6ab Suppress unexpected
        8e9f4a2 Suppress