Felipe writes:

usb: changes for v4.15 merge window

Not much going on this time around. With only 51 non-merge commits,
this was one of the smallest pull requests from the Gadget tree.

Most of the changes are in the mtu3 driver which added support for
36-bit DMA, support for USB 3.1 and support for dual-role (along with
some non-critical fixes).

The dwc2 driver got a few improvements to how we handle gadget state
tracking and also added support for STM32F7xx devices.

Other than that, we just some minor non-critical fixes and
improvements all over the place.