mac80211: remove description of dropped member

Commit 976bd9ef ("mac80211: move beacon_loss_count into ifmgd")
removed the member from the sta_info struct but the description stayed
lingering. Remove it.
Signed-off-by: Luis de Bethencourt <luisbg@osg.samsung.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

net/mac80211/sta_info.h

@@ -377,7 +377,6 @@ DECLARE_EWMA(signal, 1024, 8)
  * @uploaded: set to true when sta is uploaded to the driver
  * @sta: station information we share with the driver
  * @sta_state: duplicates information about station state (for debug)
- * @beacon_loss_count: number of times beacon loss has triggered
  * @rcu_head: RCU head used for freeing this station struct
  * @cur_max_bandwidth: maximum bandwidth to use for TX to the station,
  *	taken from HT/VHT capabilities or VHT operating mode notification