Encapsulate MCA bus attach logic into mcabus_attach().

Merge thorpej-cfargs2.

branches: 1.21.8;
Merge thorpej-cfargs branch:

Simplify and make extensible the config_search() / config_found() /
config_attach() interfaces: rather than having different variants for
which arguments you want pass along, just have a single call that
takes a variadic list of tag-value arguments.

Adjust all call sites:
- Simplify wherever possible; don't pass along arguments that aren't
actually needed.
- Don't be explicit about what interface attribute is attaching if
the device only has one. (More simplification.)
- Add a config_probe() function to be used in indirect configuiration
situations, making is visibly easier to see when indirect config is
in play, and allowing for future change in semantics. (As of now,
this is just a wrapper around config_match(), but that is an
implementation detail.)

Remove unnecessary or redundant interface attributes where they're not
needed.

There are currently 5 "cfargs" defined:
- CFARG_SUBMATCH (submatch function for direct config)
- CFARG_SEARCH (search function for indirect config)
- CFARG_IATTR (interface attribte)
- CFARG_LOCATORS (locators array)
- CFARG_DEVHANDLE (devhandle_t - wraps OFW, ACPI, etc. handles)

...and a sentinel value CFARG_EOL.

Add some extra sanity checking to ensure that interface attributes
aren't ambiguous.

Use CFARG_DEVHANDLE in MI FDT, OFW, and ACPI code, and macppc and shark
ports to associate those device handles with device_t instance. This
will trickle trough to more places over time (need back-end for pre-OFW
Sun OBP; any others?).

branches: 1.20.68;
#include <sys/bus.h> instead of <machine/bus.h>.

On x86, change the bus_space_tag_t to a pointer to a struct
bus_space_tag. For now, bus_space_tag's only member is
bst_type, the type of space, which is either X86_BUS_SPACE_IO
or X86_BUS_SPACE_MEM. In the future, new bus_space_tag members
will refer to override-functions installed by a new function,
bus_space_tag_create(9).

Add pointers to constant struct bus_space_tag, x86_bus_space_io and
x86_bus_space_mem. Use them to replace most uses of X86_BUS_SPACE_IO
and X86_BUS_SPACE_MEM.

Add an x86-specific bus_space_is_equal(9) implementation that compares
the two tags' bst_type.

branches: 1.18.14; 1.18.20; 1.18.22;
device_t/softc split and other related cosmetic changes.

Remove clause 3 and 4 from TNF licenses

branches: 1.16.2; 1.16.4;
use aprint_*_dev and device_xname
OK joerg

branches: 1.15.52;
__unused removal on arguments; approved by core.

- sprinkle __unused on function decls.
- fix a couple of unused bugs
- no more -Wno-unused for i386

branches: 1.13.14; 1.13.16;
Use aprint_*().

branches: 1.12.2; 1.12.4; 1.12.6;
merge ktrace-lwp.

branches: 1.11.6;
de-__P, partially ANSIfy

branches: 1.10.4; 1.10.6;
Phase out the use of a string as first "attach args" member to control
which bustype should be attached with a specific call to config_found()
(from a "mainbus" or a bus bridge).
Do it for isa/eisa/mca and pci/agp for now. These buses all attach to
an mi interface attribute "isabus", "eisabus" etc., and the autoconf
framework now allows to specify an interface attribute on config_found()
and config_search(), which limits the search of matching config data
to these which attach to that specific attribute.
So we basically have to call config_found_ia(..., "foobus", ...) where
such a bus is attached.
As a consequence, where a "mainbus" or alike also attaches other
devices (eg CPUs) which do not attach to a specific attribute yet,
we need at least pass an attribute name (different from "foobus") so
that the foo bus is not found at these places. This made some minor
changes necessary which are not obviously related to the mentioned buses.

pass string length (= boundary info) to pci_devinfo so that we do not run over
the end of memory region

branches: 1.8.2;
Adapt for i386/x86 change.

Use aprint_normal() for cfprint routines.

Tidy up CFATTACH_DECL() formatting.

Merge Bill Sommerfeld's i386 MP branch. This code has some known
caveats, but works quite well in a lot of MP cases, and all
UP cases that I have tested. Parts of this will hopefully be
reworked in the not-too-distant future.

Declare all cfattach structures const.

branches: 1.3.2;
add RCSID

branches: 1.2.4;
Match any device with class bridge and subclass BRIDGE_MC, instead
of matching individual products. Pointed out by Jason Thorpe.

branches: 1.1.2; 1.1.4; 1.1.6;
Add an autoconfig node for PCI-MCA bridges. Configures MCA bridges
via callback. This beast is very rare, present only on some IBM PCs.
Code was copied off pceb.