wifi: cfg80211: add missing kernel-doc for cqm_rssi_work

As reported by Stephen, I neglected to add the kernel-doc
for the new struct member. Fix that.
Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Fixes: 37c20b2e ("wifi: cfg80211: fix cqm_config access race")
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

include/net/cfg80211.h

@@ -5941,6 +5941,7 @@ void wiphy_delayed_work_cancel(struct wiphy *wiphy,
  * @event_lock: (private) lock for event list
  * @owner_nlportid: (private) owner socket port ID
  * @nl_owner_dead: (private) owner socket went away
+ * @cqm_rssi_work: (private) CQM RSSI reporting work
  * @cqm_config: (private) nl80211 RSSI monitor state
  * @pmsr_list: (private) peer measurement requests
  * @pmsr_lock: (private) peer measurements requests/results lock