The input file used to have a $FreeBSD$ tag on the first line and we
recorded that in the generated files to know which versions they were
based on. With the removal of all that the logic was not quite correct
anymore; fix that.
While here generate defined names which match the ones in the Linux
drivers; given we are likely to have drivers only based on those
one way or another there is absolutely no reason to fight over differently
generated names for device and vendor IDs.
Sponsored by: The FreeBSD Foundation
MFC after: 3 days