[strongSwan] ikev1/psk for l2tp broken in 5.2.1

[Tobias Brunner]

Hi Lars,

> conn psk-l2tp
>         keyexchange=ikev1
>         authby=psk
>         rekey=no
>         type=tunnel

Try type=transport.  The clients are most likely to propose that and
5.2.1 now checks that the proposed mode is the one that is configured.

Regards,
Tobias