Staging: rtl8723bs: remove useless structs in wifi.h

Remove the following unreferenced struct in include/wifi.h:

	struct rtw_ieee80211_bar

Signed-off-by: Marco Cesati <marcocesati@gmail.com>
Link: https://lore.kernel.org/r/20210322133717.17797-15-marcocesati@gmail.com


Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>