When we receive Device Discoverability Response, we need to initiate
new GO Negotiation as quickly as possible to avoid the target client
from going back to sleep. Make sure we do not end up in
P2P_CONNECT_LISTEN state (short Listen mode) in this case.
While this is not strictly speaking required by the P2P specification
for a not-P2P Managed Device, this can provide useful information for
the P2P manager AP and may be needed to pass certification tests.
While there is no real value in this, the spec seems to mark this
attribute as mandatory from GO, so better included it regardless
of whether we have clients or not (the attribute is empty in case
no clients are connected).
"wpa_cli p2p_set peer_filter <MAC address>" can now be used to
only allow a single P2P Device (based on P2P Device Address) to be
discovered for testing. Setting the address to 00:00:00:00:00:00
disables the filter.