Make use of the IEEE80211_TX_RC_DUP_DATA flag to duplicate a
transmission with legacy rates to both 20Mhz channels if set.
Also update the related comment in rt2800.h to describe the
behavior of the BW_40 flag for legacy rates.
Signed-off-by: NHelmut Schaa <helmut.schaa@googlemail.com>
Signed-off-by: NIvo van Doorn <IvDoorn@gmail.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>