P2P: Add event messages for possible PSK failures on P2P groups

P2P: Add event messages for possible PSK failures on P2P groups

It is possible for the GO of a persistent group to change the PSK or
remove a client when per-client PSKs are used and this can happen
without the SSID changing (i.e., the group is still valid, but just not
for a specific client). If the client side of such persistent group ends
up trying to use an invalidated persistent group information, the
connection will fail in 4-way handshake. A new WPS provisioning step is
needed to recover from this.

Detect this type of case based on two 4-way handshake failures when
acting as a P2P client in a persistent group. A new
"P2P-PERSISTENT-PSK-FAIL id=<persistent group id>" event is used to
indicate when this happens. This makes it easier for upper layers to
remove the persistent group information with "REMOVE_NETWORK <persistent
group id>" if desired (e.g., based on user confirmation).

In addition to indicating the error cases for persistent groups, all
this type of PSK failures end up in the client removing the group with
the new reason=PSK_FAILURE information in the P2P-GROUP-REMOVED event.

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