staging: wilc1000: remove unnecessary elements from 'wilc_priv' struct

Remove unused elements from 'wilc_priv' structure.

Signed-off-by: Ajay Singh <ajay.kathat@microchip.com>
Reviewed-by: Claudiu Beznea <claudiu.beznea@microchip.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>