Copy head (r256279) to stable/10 as part of the 10.0-RELEASE cycle.

Approved by: re (implicit)
Sponsored by: The FreeBSD Foundation

Replace all calls to minor() with dev2unit().

After I removed all the unit2minor()/minor2unit() calls from the kernel
yesterday, I realised calling minor() everywhere is quite confusing.
Character devices now only have the ability to store a unit number, not
a minor number. Remove the confusion by using dev2unit() everywhere.

This commit could also be considered as a bug fix. A lot of drivers call
minor(), while they should actually be calling dev2unit(). In -CURRENT
this isn't a problem, but it turns out we never had any problem reports
related to that issue in the past. I suspect not many people connect
more than 256 pieces of the same hardware.

Reviewed by: kib

Since DELAY() was moved, most <machine/clock.h> #includes have been
unnecessary.

Remove bus_{mem,p}io.h and related code for a micro-optimization on i386
and amd64. The optimization is a trivial on recent machines.

Reviewed by: -arch (imp, marcel, dfr)

Skip PNP probes. If there are isapnp or pnpbios instances of this driver,
then we can support them later. This keeps the pbio probe from claiming
lots of otherwise unused pnpbios devices on my laptop.

Start each of the license/copyright comments with /*-, minor shuffle of lines

Catch up with the header repo copy.

Fix conflicts I didn't fix before I committed my busspace changes.

Noticed by: ru@ (and likely tinderbox, I haven't checked)

Convert to newbus. (chances are we could now move this to dev/pbio
since I believe it is now MI, but that hasn't been done yet).

Reviewed by: dds

style(9)

Port pbio to HEAD.

OK'd by: dds