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

The following patch fixes the checkpatch.pl warning:

drivers/staging/rtl8723au/core/rtw_security.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_security.c

@@ -259,8 +259,6 @@ void rtw_wep_decrypt23a(struct rtw_adapter *padapter,
 			  crc[1], payload[length - 3],
 			  crc[0], payload[length - 4]));
 	}
-
-	return;
 }
 
 /* 3		===== TKIP related ===== */