staging: speakup: Fix comment block coding style

This is a patch to the spk_ttyio.c file that fix up a comment block
warninig, found by checkpatch.pl tool, by adding */ on a separte line.

WARNING: Block comments use a trailing */ on a separate line

Signed-off-by: Mihaela Muraru <mihaela.muraru21@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>