Start autoscan for first connection attempt

Start autoscan for first connection attempt

Use wpa_supplicant_set_state() to initialize state to DISCONNECT so that
autoscan gets initialized properly. This needs a change in
autoscan_init() to avoid extra scan request that would postpone the
first scan request when an interface is added.

Signed-hostap: Jouni Malinen <j@w1.fi>