mac80211: Add support for QoS mapping

Implement set_qos_map() handler for mac80211 to enable QoS mapping
functionality.

Signed-off-by: Kyeyoon Park <kyeyoonp@qca.qualcomm.com>
Signed-off-by: Jouni Malinen <jouni@qca.qualcomm.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>