openvswitch: use after free in __ovs_ct_free_action()

We free "ct_info->ct" and then use it on the next line when we pass it
to nf_ct_destroy_timeout().  This patch swaps the order to avoid the use
after free.

Fixes: 06bd2bdf

 ("openvswitch: Add timeout support to ct action")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Acked-by: Yi-Hung Wei <yihung.wei@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>