Since the WMI API has been added and we can detect from the
FW IEs what firmware variant we deal with, turn on support
for 10.x firmware branch in ath10k_wmi_attach().

kvalo: improve the commit log
Signed-off-by: Bartosz Markowski <bartosz.markowski@tieto.com>
Signed-off-by: Kalle Valo <kvalo@qca.qualcomm.com>