staging: wfx: fix support for CSA

The WF200 is able to filter beacons. However, it uses a positive filter:
any change to an IE not listed won't be reported.

In current code, the changes in Channel Switch Announcement (CSA) are
not reported to the host. Thus, it fixes the support for CSA in station
mode.

Signed-off-by: Jérôme Pouiller <jerome.pouiller@silabs.com>
Link: https://lore.kernel.org/r/20210913130203.1903622-11-Jerome.Pouiller@silabs.com


Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>