Linux 4.17 rc5

Things continue to look fairly normal. About half the rc5 release is driver
updates, with amdgpu standing out but mainly because everything else is
really pretty small, not because the amdgpu patches are all that big.

Outside of drivers, there's a random collection of changes all over: some
filesystems (ceph and cifs), some networking, some core kernel, some small
arch updates, and some tooling.

There's a fair number of changes in there (shortlog appended as usual), but
a lot of them really are one- or two-liners.

So I think we're in pretty good shape. Please go keep testing, though, to
make sure we're not missing anything.