staging: wilc1000: avoid setting default value for variable at declaration

Cleanup patch to avoid setting default value for local variables and
also clubbed similar variables together.

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>