ath10k: add support for firmware newer than 636

The mgmt_rx event structure has been expanded.
Since the structure header is expanded the payload
(i.e. mgmt frame) is shifted by a few bytes. This
needs to be taken into account in order to support
both old and new firmware.

This introduces a fw_features to keep track of any
FW-related ABI/behaviour changes.

Signed-off-by: Michal Kazior <michal.kazior@tieto.com>
Signed-off-by: Kalle Valo <kvalo@qca.qualcomm.com>
ath10k: add support for HTT 3.0

New firmware comes with new HTT protocol version.
In 3.0 the separate mgmt tx command has been
removed. All traffic is to be pushed through data
tx (tx_frm) command with a twist - FW seems to not
be able (yet?) to access tx fragment table so for
manamgement frames frame pointer is passed
directly.

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