ipsec: filtertunnel kind of helps, but is the wrong approach

(cherry picked from commit 50f2ffad)

src/etc/inc/system.inc

@@ -130,8 +130,6 @@ function activate_sysctls()
     global $config;
 
     $sysctls = array(
-        'net.inet.ipsec.filtertunnel' => '1',
-        'net.inet6.ipsec6.filtertunnel' => '1',
         'net.enc.in.ipsec_bpf_mask' => '2', /* after processing */
         'net.enc.in.ipsec_filter_mask' => '2', /* after processing */
         'net.enc.out.ipsec_bpf_mask' => '1', /* before processing */