usb4bsd: Bring in FreeBSD's libusbhid, usbhidctl and USB kernel code. In order to make it live peacefully along with our old USB code, name all directories with new USB code *u4b* instead of *usb*. This is FreeBSD SVN r231881. Submitted-by: Markus Pfeiffer <markus.pfeiffer@morphism.de>