_bus.h: Use standard licnese text

All of these used the 'immediately at beginning' variation of the
BSD-2-Clause license. This wasn't intentional, just what I copied from
from a random file in the tree back in 2005. It was not an intentional
decision.

The different arch bus.h files are a mix of BSD-2-Clause and
BSD-4-Clause that have various copyright holders (Charles M. Hannum,
Christopher G. Demetriou, The NetBSD Foundation and KATO Takenori), and
some of the content of these files were likely copied from there.
However, apart from the uncopyrightable interface lines, there are very
few comments. It's unclear if these comments are 'original material'
here to copyright, but to the extent that there is, license it under the
standard BSD-2-Clause copyright that's the norm for the project today.
In any event, the standard BSD-2-Clause is also closer to those
originals.

In addition, FreeBSD uses different type definitions than the original
NetBSD code in part. The comments that were copied have been copied a
lot, but appear in NetBSD's bus.h files in NetBSD 1.3.

While I'm here, assign the copyright, to the extent any exists from me,
to the FreeBSD Foundation. I just cut and pasted these into _bus.h from
the different machine files and those files have a rich history of
modification from the original imports from NetBSD over more than 25
years so it's tricky to say who, exactly, wrote each bit. Given the size
of the files, this seems like the best compromise. Also add an
acknowledgement to the NetBSD 1.3 bus.h files and their authors (there
were no additional FreeBSD authors listed in the various
sys/*/include/bus.h files). Finally, use the SPDX identifier instead of
multiple copies of the text.

Differential Revision: https://reviews.freebsd.org/D42532
Sponsored by: Netflix

sys: Remove $FreeBSD$: two-line .h pattern

Remove /^\s*\*\n \*\s+\$FreeBSD\$$\n/

spdx: The BSD-2-Clause-FreeBSD identifier is obsolete, drop -FreeBSD

The SPDX folks have obsoleted the BSD-2-Clause-FreeBSD identifier. Catch
up to that fact and revert to their recommended match of BSD-2-Clause.

Discussed with: pfg
MFC After: 3 days
Sponsored by: Netflix

Regularize my copyright notice

o Remove All Rights Reserved from my notices
o imp@FreeBSD.org everywhere
o regularize punctiation, eliminate date ranges
o Make sure that it's clear that I don't claim All Rights reserved by listing
All Rights Reserved on same line as other copyright holders (but not
me). Other such holders are also listed last where it's clear.

Remove 'All Rights Reserved.' from all of my Copyrights in sys/arm and
always use 'M. Warner Losh' for consistency.

'All Rights Reserved.' was prescribed by the Buenos Aires Copyright
Convention of 1910, but has been mostly dead since the early 1990's
and completely meaningless since 2000 when Nicaragua ratified the
Berne convention.

Some files not done due to ambiguity of various types.

sys/arm: further adoption of SPDX licensing ID tags.

Mainly focus on files that use BSD 2-Clause license, however the tool I
was using misidentified many licenses so this was mostly a manual - error
prone - task.

The Software Package Data Exchange (SPDX) group provides a specification
to make it easier for automated tools to detect and summarize well known
opensource licenses. We are gradually adopting the specification, noting
that the tags are considered only advisory and do not, in any way,
superceed or replace the license texts.

A new jail(8) with a configuration file, to replace the work currently done
by /etc/rc.d/jail.

- Import the HEAD csup code which is the basis for the cvsmode work.

Remove errant % in license comment.

MFC after: 3 days

Break out the definition of bus_space_{tag,handle}_t and a few other types
into _bus.h to help with name space polution from including all of bus.h.
In a few days, I'll commit changes to the MI code to take advantage of thse
sepration (after I've made sure that these changes don't break anything in
the main tree, I've tested in my trees, but you never know...).

Suggested by: bde (in 2002 or 2003 I think)
Reviewed in principle by: jhb