staging: wilc1000: validate cfg parameters before scheduling the work

Validate cfg parameters after being called by cfg80211 in set_wiphy_params
before scheduling the work executed in handle_cfg_param

Signed-off-by: Adham Abozaeid <adham.abozaeid@microchip.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>