staging/speakup: Update TODO list

staging/speakup: Update TODO list

Thanks to Okash's latest work, the TODO list is essentially empty, so
the way out from staging now seems open.

The status of the remaining issue mentioned in TODO is not clear, we
asked the speakup user mailing list for reproducer cases, but didn't get
a really specific scenario. One serious bug was fixed by 9d32c0cde4e2
("staging/speakup: fix get_word non-space look-ahead"), which does not
seem to really be related to the bug mentioned in TODO. Possibly the bug
mentioned in TODO has been fixed long ago and people have been thinking
that it was not because they can not distinguish the symptoms mentioned
in TODO from the symptoms of the bug fixed by 9d32c0cde4e2.

Signed-off-by: Samuel Thibault <samuel.thibault@ens-lyon.org>
Link: https://lore.kernel.org/r/20200726165452.qhos3wrjcm6jmcmx@function
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>