Staging: Update parameters for cfg80211 key management operation

Commit e31b8213 ("cfg80211/mac80211:
allow per-station GTKs") changed the signatures of these operations
but did not update the staging drivers.

Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>