usb4bsd: Add FreeBSD revisions to files
truephy: Clean up some leftover debug kprintf
net/if_clone: Panic if the same cloner is attached twice

if_clone_attach used to allow attaching the same cloner twice,
which then lead to infinite loops when trying to create
a clone with an invalid name.
This patch adds a check whether the cloner is already
attached, and if so, panics.
Remove the old USB stack and related userland, etc.

As detailed in UPDATING, users with a custom configuration file which
was derived from a *GENERIC file before we made usb4bsd default (this
happened in 3.6) might need to remove or comment out a couple of
devices which are now unknown.
kernel: Remove two more oldusb remains.