staging: wfx: allow to scan networks

Chip can make foreground scan or background, but both can't be mixed in
same request. So, we need to split each mac80211 requests into multiple
HIF requests.

Signed-off-by: Jérôme Pouiller <jerome.pouiller@silabs.com>
Link: https://lore.kernel.org/r/20190919142527.31797-19-Jerome.Pouiller@silabs.com


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