staging: wfx: update TODO

Update the TODO list associated to the wfx driver with the last
progresses and last remarks made by reviewers.

The items about support for P2P and mesh have also been removed. Indeed,
it seems that the device does not fully support them.

Signed-off-by: Jérôme Pouiller <jerome.pouiller@silabs.com>
Link: https://lore.kernel.org/r/20200415161147.69738-21-Jerome.Pouiller@silabs.com


Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>