PMKSA: Make deauthentication due to cache entry removal more granular

PMKSA: Make deauthentication due to cache entry removal more granular

Expiry can always trigger a deauthentication, but otherwise,
deauthentication should only happen when the *current* cache entry is
removed and not being replaced. It should not happen when the current
PMK just happens to match the PMK of the entry being removed, since
multiple entries can have the same PMK when OKC is used and these
entries are often removed at different times.

This fixes an issue where eviction of the oldest inactive entry due to
adding a newer entry to a full cache caused a deauthentication when the
entry being removed had the same PMK as the current entry.

Signed-hostap: Dan Williams <dcbw@redhat.com>