Port autofs to DragonFly

[Tomohiro Kusumi]

The VFS change I made (which is kinda sensitive one) was accepted by Matt,
so I'll be committing autofs to master in a few days.


2016-05-26 10:17 GMT+09:00 Tomohiro Kusumi <kusumi.tomohiro at gmail.com>:
> The code has been tested by a user.
> A simple configuration works without issues just like it did on my machines.
>
> If it works the same with more complex configurations the user
> normally uses, and if one VFS change I made to nlookup() (which
> doesn't affect or used by other filesystems) is acceptable by Matt,
> I'd like autofs to go into master for upcoming 4.6.
>
> I'll make the code without bunch of debug kprintfs available hopefully
> in a few days.