staging: wilc1000: remove obsolete TODO file

The movement of wilc1000 out of staging left an obsolete TODO file.

Remove that as it's no longer needed.

Cc: Kalle Valo <kvalo@codeaurora.org>
Cc: <Ajay.Kathat@microchip.com>
Cc: <Venkateswara.Kaja@microchip.com>
Cc: <Sripad.Balwadgi@microchip.com>
Cc: <Nicolas.Ferre@microchip.com>
Cc: <johannes@sipsolutions.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>