staging: wilc1000: return kernel error codes from wilc_wlan_stop

return -EIO for bus failures, 0 otherwise.

Signed-off-by: Adham Abozaeid <adham.abozaeid@microchip.com>
Link: https://lore.kernel.org/r/20190809182510.22443-3-adham.abozaeid@microchip.com


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