ath10k: fix pmf for wmi-tlv on qca6174

New wmi-tlv firmware uses HTT 3.0 protocol which
uses TX_FRM command for management frames (instead
of a dedicated command). To support PMF it is
necessary to provide explicit tailroom.

Signed-off-by: Marek Kwaczynski <marek.kwaczynski@tieto.com>
Signed-off-by: Michal Kazior <michal.kazior@tieto.com>
Signed-off-by: Kalle Valo <kvalo@qca.qualcomm.com>