[strongSwan] upgrade from 4.5.2 to 5.2.1 breaks phase 2 authentication

[Tobias Brunner]

> Tue Jul 10 08:44:05 2018 (GMT -0400): [SRX5308] [IKE] INFO:  Sending Informational Exchange: notify
> payload[ATTRIBUTES-NOT-SUPPORTED]
> Tue Jul 10 08:44:05 2018 (GMT -0400): [SRX5308] [IKE] ERROR:  mismatched ID was returned.

I suppose this means it doesn't like the returned subnets.  So check
your left|rightsubnet settings for this connection.  On both sides,
because this looks a bit strange:

> Tue Jul 10 08:44:05 2018 (GMT -0400): [SRX5308] [IKE] INFO:  Using IPsec SA configuration:
> 192.168.11.1/24<->192.168.100.1/24

.1/24 is technically the same as .0/24 but perhaps this box wants an
exact match, which strongSwan won't provide.

Regards,
Tobias