usb: isp1760: Add device controller support

The ISP1761 is a dual-mode host and device controller backward
compatible on the host side with the ISP1760. Add support for the device
controller.

Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>
7 files changed