Revert "wcn36xx: Enable firmware link monitoring"

Firmware link offload monitoring can be made to work in 3/4 cases by
switching on firmware feature bit WLANACTIVE_OFFLOAD

- Secure power-save on
- Secure power-save off
- Open power-save on

However, with an open AP if we switch off power-saving - thus never
entering Beacon Mode Power Save - BMPS, firmware never forwards loss
of beacon upwards.

We had hoped that WLANACTIVE_OFFLOAD and some fixes for sequence numbers
would unblock this but, it hasn't and further investigation is required.

Its possible to have a complete set of Secure power-save on/off and Open
power-save on/off provided we use Linux' link monitoring mechanism.

While we debug the Open AP failure we need to fix upstream.

This reverts commit c973fdad79f6eaf247d48b5fc77733e989eb01e1.

Signed-off-by: Bryan O'Donoghue <bryan.odonoghue@linaro.org>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
Link: https://lore.kernel.org/r/20211025093037.3966022-2-bryan.odonoghue@linaro.org