nl80211: Indicate disconnect event as deauthentication

nl80211: Indicate disconnect event as deauthentication

This was previously indicated as disassociation, but the P2P group
session ending case expect a deauthentication notification. Since the
cfg80211 disconnection event does not really indicate which frame was
used, the easiest approach for now seems to be to just indicate these
as deauthentication events.

Signed-hostap: Jouni Malinen <jouni@qca.qualcomm.com>