sip: set incoming call secure state

Change-Id: I802006aa7a139413da6e857e2030f817d06e9941
Reviewed-by: Andreas Traczyk <andreas.traczyk@savoirfairelinux.com>
Reviewed-by: Guillaume Roguez <guillaume.roguez@savoirfairelinux.com>

src/sip/sipvoiplink.cpp

@@ -294,6 +294,7 @@ transaction_request_cb(pjsip_rx_data *rdata)
         }
     }
     call->setTransport(transport);
+    call->setSecure(transport->isSecure());
 
     // FIXME : for now, use the same address family as the SIP transport
     auto family = pjsip_transport_type_get_af(pjsip_transport_get_type_from_flag(transport->get()->flag));