dpp: set new_freq when configuring as initiator

This is used to hold the current BSS frequency which will be
used after IWD receives a presence announcement. Since this was
not being set, the logic was always thinking there was a channel
mismatch (0 != current_freq) and attempting to go offchannel to
'0' which resulted in -EINVAL, and ultimately protocol termination.

src/dpp.c

@@ -2436,6 +2436,8 @@ static struct l_dbus_message *dpp_start_configurator_common(
 
 		if (!dpp->mcast_support)
 			dpp->state = DPP_STATE_AUTHENTICATING;
+
+		dpp->new_freq = bss->frequency;
 	} else
 		dpp->current_freq = bss->frequency;