DPP: Initialize conf_resp_status to non-OK

DPP: Initialize conf_resp_status to non-OK

This avoids unexpected behavior if GAS query fails and the Config
Response does not get processed at all. Previously, this could result in
configuration being assumed to be successful instead of failure when
Config Response object was not received at all. That could result in
undesired Config Result frame transmission with DPP Rel 2 and not
clearing the ongoing DPP session.

Signed-off-by: Jouni Malinen <jouni@codeaurora.org>