man: corosync.conf seqno_unchanged_const description incorrect

seqno_unchanged_const is used to determine when the rep should hold the
token. The merge detection timeout is started after any idle rotation of
the token.

Signed-off-by: Tim Beale <tlbeale@gmail.com>
Reviewed-by: Jan Friesse <jfriesse@redhat.com>

man/corosync.conf.5

@@ -385,7 +385,7 @@ The default is 2500 failures to receive a message.
 .TP
 seqno_unchanged_const
 This constant specifies how many rotations of the token without any multicast
-traffic should occur before the merge detection timeout is started.
+traffic should occur before the hold timer is started.
 
 The default is 30 rotations.