staging: rtl8192u: remove the repeated declaration

Functions 'ieee80211_stop_send_beacons' and 'notify_wx_assoc_event'
are declared twice in their header file, so remove the repeated
declaration.

Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Shaokun Zhang <zhangshaokun@hisilicon.com>
Link: https://lore.kernel.org/r/1622446678-52652-1-git-send-email-zhangshaokun@hisilicon.comSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/staging/rtl8192u/ieee80211/ieee80211.h

@@ -2249,10 +2249,8 @@ void ieee80211_wake_queue(struct ieee80211_device *ieee);
 void ieee80211_stop_queue(struct ieee80211_device *ieee);
 struct sk_buff *ieee80211_get_beacon(struct ieee80211_device *ieee);
 void ieee80211_start_send_beacons(struct ieee80211_device *ieee);
-void ieee80211_stop_send_beacons(struct ieee80211_device *ieee);
 int ieee80211_wpa_supplicant_ioctl(struct ieee80211_device *ieee,
 				   struct iw_point *p);
-void notify_wx_assoc_event(struct ieee80211_device *ieee);
 void ieee80211_ps_tx_ack(struct ieee80211_device *ieee, short success);
 
 void softmac_mgmt_xmit(struct sk_buff *skb, struct ieee80211_device *ieee);