ath10k: implement prb tmpl wmi command

New firmware revisions with beacon templates need
probe templates as well because they don't forward
probe requests to host at all.

This is required for new firmware to work with
direct probe requests (notably required by hidden
ssid AP).

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