Linux 4.17 rc6

Things continue to be fairly calm. There's a couple of commits in here that
aren't "trivial few-liners", but most of it really is pretty small. And in
fact, a quarter of the full patch for the week is tooling - and the bulk of
that is the testing subdirectory.

In fact, drivers are in the minority here, because another 30% is arch
updates (arm, s390, x86), and we even have more lines of filesystem fixes
than we have driver fixes (admittedly mostly due to a few of the
more-than-a-few-liner patches being to filesystems: afs and btrfs).

We do have a few driver fixes (all over - hwmon, usb, sound, acpi, gpu),
but it's all really small.

So nothing special to report. Go read the shortlog, pull the changes,
build, and test. It should all be good and pretty stable by this point.