Convert pci_delete_child() to a bus_child_deleted() method.

Instead of providing a wrapper around device_delete_child() that the PCI
bus and child bus drivers must call explicitly, move the bulk of the logic
from pci_delete_child() into a bus_child_deleted() method
(pci_child_deleted()). This allows PCI devices to be safely deleted via
device_delete_child().
- Add a bus_child_deleted method to the ACPI PCI bus which clears the
device_t associated with the corresponding ACPI handle in addition to
the normal PCI bus cleanup.
- Change cardbus_detach_card to call device_delete_children() and move
CardBus-specific delete logic into a new cardbus_child_deleted() method.
- Use device_delete_child() instead of pci_delete_child() in the SRIOV code.
- Add a bus_child_deleted method to the OpenFirmware PCI bus drivers which
frees the OpenFirmware device info for each PCI device.

To preserve KBI, a pci_delete_child() function is left in place that
just calls device_delete_child().

PR: 226562
Requested by: dexuan

MFC 292669:
Add accessor methods to fetch the BAR holding the MSI-X table and PBA.

While here, explicitly note the requirement that the BAR(s) must be
allocated prior to calling pci_alloc_msix().

MFC r270212,r270332:

This helps reduce the diff in pci(4) between head and stable/10 to help pave
the way for bringing in IOV/nv(9) more cleanly

Differential Revision: https://reviews.freebsd.org/D4728
Relnotes: yes
Reviewed by: hselasky (ofed piece), royger (overall change)
Sponsored by: EMC / Isilon Storage Division

r270212 (by royger):

pci: make MSI(-X) enable and disable methods of the PCI bus

Make the functions pci_disable_msi, pci_enable_msi and pci_enable_msix
methods of the newbus PCI bus. This code should not include any
functional change.

Sponsored by: Citrix Systems R&D
Reviewed by: imp, jhb
Differential Revision: https://reviews.freebsd.org/D354

dev/pci/pci.c:
- Convert the mentioned functions to newbus methods.
- Fix the callers of the converted functions.

sys/dev/pci/pci_private.h:
dev/pci/pci_if.m:
- Declare the new methods.

dev/pci/pcivar.h:
- Add helpers to call the newbus methods.

ofed/include/linux/pci.h:
- Add define to prevent the ofed version of pci_enable_msix from
clashing with the FreeBSD native version.

r270332 (by royger):

pci: add a new pci_child_added newbus method.

This is needed so when running under Xen the calls to pci_child_added
can be intercepted and a custom Xen method can be used to register
those devices with Xen. This should not include any functional
change, since the Xen implementation will be added in a following
patch and the native implementation is a noop.

Sponsored by: Citrix Systems R&D
Reviewed by: jhb

dev/pci/pci.c:
dev/pci/pci_if.m:
dev/pci/pci_private.h:
dev/pci/pcivar.h:
- Add the pci_child_added newbus method.

MFC 261790:
Add support for managing PCI bus numbers. As with BARs and PCI-PCI bridge
I/O windows, the default is to preserve the firmware-assigned resources.
PCI bus numbers are only managed if NEW_PCIB is enabled and the architecture
defines a PCI_RES_BUS resource type.
- Add a helper API to create top-level PCI bus resource managers for each
PCI domain/segment. Host-PCI bridge drivers use this API to allocate
bus numbers from their associated domain.
- Change the PCI bus and CardBus drivers to allocate a bus resource for
their bus number from the parent PCI bridge device.
- Change the PCI-PCI and PCI-CardBus bridge drivers to allocate the
full range of bus numbers from secbus to subbus from their parent bridge.
The drivers also always program their primary bus register. The bridge
drivers also support growing their bus range by extending the bus resource
and updating subbus to match the larger range.
- Add support for managing PCI bus resources to the Host-PCI bridge drivers
used for amd64 and i386 (acpi_pcib, mptable_pcib, legacy_pcib, and qpi_pcib).
- Define a PCI_RES_BUS resource type for amd64 and i386.

PR: 197076

MFC r257072:
Make pci_get_dma_tag() non-static.

Approved by: re (glebius)

MFC 261790:
Add support for managing PCI bus numbers. As with BARs and PCI-PCI bridge
I/O windows, the default is to preserve the firmware-assigned resources.
PCI bus numbers are only managed if NEW_PCIB is enabled and the architecture
defines a PCI_RES_BUS resource type.
- Add a helper API to create top-level PCI bus resource managers for each
PCI domain/segment. Host-PCI bridge drivers use this API to allocate
bus numbers from their associated domain.
- Change the PCI bus and CardBus drivers to allocate a bus resource for
their bus number from the parent PCI bridge device.
- Change the PCI-PCI and PCI-CardBus bridge drivers to allocate the
full range of bus numbers from secbus to subbus from their parent bridge.
The drivers also always program their primary bus register. The bridge
drivers also support growing their bus range by extending the bus resource
and updating subbus to match the larger range.
- Add support for managing PCI bus resources to the Host-PCI bridge drivers
used for amd64 and i386 (acpi_pcib, mptable_pcib, legacy_pcib, and qpi_pcib).
- Define a PCI_RES_BUS resource type for amd64 and i386.

PR: 197076

MFC r257072:
Make pci_get_dma_tag() non-static.

Approved by: re (glebius)