Added MSI/MSI-X and interrupt_distribute(9) support for powerpc.

branches: 1.9.2;
PCI Extended Configuration stuff written by nonaka@:
- Add PCI Extended Configuration Space support into x86.
- Check register offset of pci_conf_read() in MD part. It returns (pcireg_t)-1
if it isn't accessible.
- Decode Extended Capability in PCI Extended Configuration Space.
Currently the following extended capabilities are decoded:
- Advanced Error Reporting
- Virtual Channel
- Device Serial Number
- Power Budgeting
- Root Complex Link Declaration
- Root Complex Event Collector Association
- Access Control Services
- Alternative Routing-ID Interpretation
- Address Translation Services
- Single Root IO Virtualization
- Page Request
- TPH Requester
- Latency Tolerance Reporting
- Secondary PCI Express
- Process Address Space ID
- LN Requester
- L1 PM Substates
The following extended capabilities are not decoded yet:
- Root Complex Internal Link Control
- Multi-Function Virtual Channel
- RCRB Header
- Vendor Unique
- Configuration Access Correction
- Multiple Root IO Virtualization
- Multicast
- Resizable BAR
- Dynamic Power Allocation
- Protocol Multiplexing
- Downstream Port Containment
- Precision Time Management
- M-PCIe
- Function Reading Status Queueing
- Readiness Time Reporting
- Designated Vendor-Specific

branches: 1.8.30;
#include <sys/bus.h> instead of <machine/bus.h>.

struct device * -> device_t
struct cfdata * -> cfdata_t
use device accessors, use device_private.
some softc/device_t splits (macppc needs a bunch more)
aprint*_dev used considerably more

branches: 1.6.52;
Merge the ppcoea-renovation branch to HEAD.

This branch was a major cleanup and rototill of many of the various OEA
cpu based PPC ports that focused on sharing as much code as possible
between the various ports to eliminate near-identical copies of files in
every tree. Additionally there is a new PIC system that unifies the
interface to interrupt code for all different OEA ppc arches. The work
for this branch was done by a variety of people, too long to list here.

TODO:
bebox still needs work to complete the transition to -renovation.
ofppc still needs a bunch of work, which I will be looking at.
ev64260 still needs to be renovated
amigappc was not attempted.

NOTES:
pmppc was removed as an arch, and moved to a evbppc target.

branches: 1.5.16; 1.5.24; 1.5.34; 1.5.36; 1.5.38; 1.5.40;
Completely rework how we look up PCI interrupts on prep:

1) Rather than build an array of the pci->intr mappings, build a proplib
tree.
2) add a SIMPLEQ of device properties to the pci_chipset_tag to hold the
proplib trees of each bus.
3) Move the interrupt routing code from pci_conf_interrupt to pci_map_intr()
4) Deal properly with non-native PCI bridge chips that are not recognized
by the prep firmware, and therefore are not noted in the residual data.

The major win of this restructure is #4. Hopefully I haven't broken
anything. Tested on a 7248-100, 7043-140 and 7024-E20.

branches: 1.4.4; 1.4.8; 1.4.14;
merge ktrace-lwp.

branches: 1.3.16;
__KERNEL_RCSID()

branches: 1.2.2;
Switch/adapt to new bus space infrastructure.

branches: 1.1.2; 1.1.8;
In order to support both indirect PCI configuration space access as well
as direct-mapped PCI configuration space access (such as implemented on
the IBM 27-82650 PCI Host Bridge), switch to a function vector based
PCI configuration space access implementation. The appropriate PCI
chipset tag is provided by platform-specific code.