devd: autofs: Move autofs related events to a separate file

[manu]

Summary

If a user don't have FreeBSD-autofs installed there is no need to try calling
automount on every GEOM event.
It's also easier to add/delete autofs related event in a separate file.

Sponsored by: Beckhoff Automation GmbH & Co. KG

[trasz]

Doesn't this also enable it by default? If so, it might be a good idea to fix the instapanic it's causing first, https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=274992.

[manu]

In D42495#970321, @trasz wrote:

Doesn't this also enable it by default? If so, it might be a good idea to fix the instapanic it's causing first, https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=274992.

It's already enabled, also can't reproduce your panic (I'm running GENERIC-NODEBUG at 2fee3974603bce6f2dc153eb6af459cb4f864ab4)