staging: wfx: simplify wfx_scan_complete()

wfx_scan_complete() do nothing with argument hif_ind_scan_cmpl. In add,
hif_ind_scan_cmpl come from hardware API and is not expected to be used
with upper layers of the driver.

Signed-off-by: Jérôme Pouiller <jerome.pouiller@silabs.com>
Link: https://lore.kernel.org/r/20200115135338.14374-40-Jerome.Pouiller@silabs.com


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