bug#25470: 26.0.50; Lock files not removed when auto-save-visited-file-name is t

[Eli Zaretskii]

> From: Philipp Stephani <p.stephani2@gmail.com>
> Date: Tue, 17 Jan 2017 20:43:33 +0100
> 
> Customize auto-save-visited-file to t, then edit a buffer and wait until
> it's auto-saved.  Even after auto-saving the lock file (.#) is still
> present.  It should be removed after a successful auto-save.

Please disregard my previous response.  I see that we clear the
buffer's modified status when we auto-save in this case, so yes, we
should also unlock the buffer's visited file.