openvswitch: Fix log message in ovs conntrack

commit 12c6bc38 upstream.

Fixes: 06bd2bdf ("openvswitch: Add timeout support to ct action")
Signed-off-by: Yi-Hung Wei <yihung.wei@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>