cfg80211/nl80211: Offload OWE processing to user space in AP mode

This interface allows the host driver to offload OWE processing
to user space. This intends to support OWE (Opportunistic Wireless
Encryption) AKM by the drivers that implement SME but rely on the
user space for the cryptographic/OWE processing in AP mode. Such
drivers are not capable of processing/deriving the DH IE.

A new NL80211 command - NL80211_CMD_UPDATE_OWE_INFO is introduced
to send the request/event between the host driver and user space.

Driver shall provide the OWE info (MAC address and DH IE) of
the peer to user space for cryptographic processing of the DH IE
through the event. Accordingly, the user space shall update the
OWE info/DH IE to the driver.

Following is the sequence in AP mode for OWE authentication.

Driver passes the OWE info obtained from the peer in the
Association Request to the user space through the event
cfg80211_update_owe_info_event. User space shall process the
OWE info received and generate new OWE info. This OWE info is
passed to the driver through NL80211_CMD_UPDATE_OWE_INFO
request. Driver eventually uses this OWE info to send the
Association Response to the peer.

This OWE info in the command interface carries the IEs that include
PMKID of the peer if the PMKSA is still valid or an updated DH IE
for generating a new PMKSA with the peer.

Signed-off-by: Liangwei Dong <liangwei@codeaurora.org>
Signed-off-by: Sunil Dutt <usdutt@codeaurora.org>
Signed-off-by: Srinivas Dasari <dasaris@codeaurora.org>
[remove policy initialization - no longer exists]
Signed-off-by: Johannes Berg <johannes.berg@intel.com>