staging: speakup: add send_xchar, tiocmset and input functionality for tty

[Okash Khawaja]

Hi,

On Fri, Apr 28, 2017 at 11:23:58PM +0200, Samuel Thibault wrote:

> So I guess now we need to be more pushy with serdev.
Haven't heard from Rob Herring yet. What do you suggest?