wifi: mac80211: add a missing comma at kernel-doc markup

The lack of the colon makes it not parse the function parameter:
	include/net/mac80211.h:6250: warning: Function parameter or member 'vif' not described in 'ieee80211_channel_switch_disconnect'

Fix it.
Signed-off-by: Mauro Carvalho Chehab <mchehab@kernel.org>
Link: https://lore.kernel.org/r/11c1bdb861d89c93058fcfe312749b482851cbdb.1656409369.git.mchehab@kernel.orgSigned-off-by: Johannes Berg <johannes.berg@intel.com>

include/net/mac80211.h

@@ -6238,7 +6238,7 @@ void ieee80211_chswitch_done(struct ieee80211_vif *vif, bool success);
 
 /**
  * ieee80211_channel_switch_disconnect - disconnect due to channel switch error
- * @vif &struct ieee80211_vif pointer from the add_interface callback.
+ * @vif: &struct ieee80211_vif pointer from the add_interface callback.
  * @block_tx: if %true, do not send deauth frame.
  *
  * Instruct mac80211 to disconnect due to a channel switch error. The channel