Merge tag 'usb-v4.8-rc1' of...

Merge tag 'usb-v4.8-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/peter.chen/usb into usb-next

Peter writes:

Hi Greg,

Below are changes for v4.8-rc1, none is important, only the documentation
update for chipidea.