Systematize handling of removed drivers.

- Every driver that was removed and whose number hasn't already been
reused is now listed with a commented-out "obsolete" line.
- The format of these has been systematized. Future format changes can
probably be safely done with a script.
- This does not include a few cases of assignments that only lasted a
couple days, or stuff from before major reorgs. Some of these may
be included nonetheless, because there was a lot of ground to cover
and therefore not a lot of time to dig into history in detail.

Note that the obsolete listings do not mean the major numbers can
never be reused; that's up to portmasters and/or core. It does mean
that they won't be reused by accident, however, which in some cases
(depending on the driver, how widely used it was, its family of device
nodes, their default permissions, etc.) can be quite dangerous.

Note that some of the things now explicitly listed as obsolete are
really ancient history. My scan went back as far as when the majors
files were added. (But not before that.)

dependant -> dependent

Remove LKMs and switch to the module framework, pass 1.

Proposed on tech-kern@.

branches: 1.3.6; 1.3.10; 1.3.16; 1.3.18;
Remove systrace. Ok core@.

branches: 1.2.28; 1.2.34; 1.2.42;
s/independant/independent/, from Zafer.

branches: 1.1.18; 1.1.22; 1.1.24;
Initial import of NetBSD/ews4800mips port,
for NEC's MIPS based EWS4800 workstations.

Most porting work was done by UCHIYAMA Yasushi <uch@netbsd>
http://mail-index.netbsd.org/port-mips/2004/06/27/0000.html
and various cleanup, updating, and fixes have been done by me.
Currently only EWS4800/350, 360, 360AD, 360ADII, 360EX and 360SX
models are supported.