ath: add support to get the detected radar specifications

This enables ath10k/ath9k drivers to collect the specifications of the
radar type once it is detected by the dfs pattern detector unit.
Usage of the collected info is specific to driver implementation.
For example, collected radar info could be used by the host driver
to send to co-processors for additional processing/validation.

Note: 'radar_detector_specs' data containing the specifications of
different radar types which was private within dfs_pattern_detector/
dfs_pri_detector is now shared with drivers as well for making use
of this information.

Signed-off-by: Sriram R <srirrama@codeaurora.org>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>