wil6210: low level RF sector API

Added vendor commands for low level control over
RF sectors. It allows user space a fine-grained control
over RF characteristics for TX and RX, such as direction
and gain of TX/RX. Main usages are debugging and diagnostics,
but also operational use cases.
API includes getting/setting a specific RF sector
configuration, as well as getting/setting the selected
sector which is used to communicate with a station.

Signed-off-by: Lior David <qca_liord@qca.qualcomm.com>
Signed-off-by: Maya Erez <qca_merez@qca.qualcomm.com>
Signed-off-by: Kalle Valo <kvalo@qca.qualcomm.com>