The rate mask code currently assumes that a rate is legacy if
IEEE80211_TX_RC_MCS is not set. This might be the cause of bogus VHT
rates being reported with minstrel_ht.
Signed-off-by: NFelix Fietkau <nbd@openwrt.org>
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>