Q35 USB initialization
- Create PCI device and initialize it as USB Host Controller (uhci or ehci)
EHCI Controller
Reference:
[1] Enhanced Host Controller Interface Specification for Universal Serial Bus
http://www.intel.co.kr/content/dam/www/public/us/en/documents/technical-specifications/ehci-specification-for-usb.pdf
[2] USB in a NutShell : http://www.beyondlogic.org/usbnutshell/usb2.shtml
[3] USB Topology : http://www.usblyzer.com/usb-topology.htm