log: Configure knet logging to the same as corosync

Before this, all knet messages, including debug, were sent
over the pipe from knet to corosync and filtered in corosync.
This was obviously a waste, so now we tell knet the logging
level we need from it and so only get the messages that the
user has requested.

Signed-off-by: Christine Caulfield <ccaulfie@redhat.com>
Reviewed-by: Jan Friesse <jfriesse@redhat.com>