staging: rtl8723au: core: rtw_ap: Fix void function return statements style warning.

The following patch fixes the checkpatch.pl warning:

drivers/staging/rtl8723au/core/rtw_ap.c WARNING: void function return statements are not generally useful
Signed-off-by: Yeliz Taneroglu <yeliztaneroglu@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/staging/rtl8723au/core/rtw_ap.c

@@ -1216,8 +1216,6 @@ static void update_bcn_wmm_ie(struct rtw_adapter *padapter)
 static void update_bcn_wps_ie(struct rtw_adapter *padapter)
 {
 	DBG_8723A("%s\n", __func__);
-
-	return;
 }
 
 static void update_bcn_p2p_ie(struct rtw_adapter *padapter)