staging: wilc1000: updated TODO list

Removed the items from WILC1000 TODO list, which are already addressed
to keep it updated. The removed items are already taken care by
previously submitted patches.

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>