staging: speakup: Fix block comment style

Use trailing */ on a separate line when it is a block comment.
This patch fixes the last of the checkpatch warnings for the file.

Signed-off-by: Janani Ravichandran <janani.rvchndrn@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>