MFC r307731: Add names for some DASP devices.

MFC 291225:
Add a new -B flag for use with list mode (-l) that lists details about
bridges. Currently this includes information about what resources a
bridge decodes on the upstream side for use by downstream devices including
bus numbers, I/O port resources, and memory resources. Windows and bus
ranges are enumerated for both PCI-PCI bridges and PCI-CardBus bridges.

To simplify the implementation, all enumeration is done by reading the
appropriate config space registers directly rather than querying the
bridge driver in the kernel via new ioctls. This does result in a few
limitations.

First, an unimplemented window in a PCI-PCI bridge cannot be accurately
detected as accurate detection requires writing to the window base
register. That is not safe for pciconf(8). Instead, this assumes that
any window where both the base and limit read as all zeroes is
unimplemented.

Second, the PCI-PCI bridge driver in a tree has a few quirks for
PCI-PCI bridges that use subtractive decoding but do not indicate that
via the progif config register. The list of quirks is duplicated in
pciconf's source.

MFC: r287522

Prefer pciids database from ports if present

Given the pciids database on ports is updated more often than the one in base
prefer this version if present, otherwise read the one from base.

Relnotes: yes
Differential Revision: https://reviews.freebsd.org/D3391

MFC r273488:
Fix some bugs in the error handling of getdevice().

PR: 194506

MFC r266468:
Add IOMMU PCI subclass, found on Tyan S8236 motherboard.

Submitted by: Dmitry Luhtionov <dmitryluhtionov@gmail.com>

MFC 260926:
Add support for displaying VPD for PCI devices via pciconf.
- Store the length of each read-only VPD value since not all values are
guaranteed to be ASCII values (though most are).
- Add a new pciio ioctl to fetch VPD for a single PCI device. The values
are returned as a list of variable length records, one for the device
name and each keyword.
- Add a new -V flag to pciconf's list mode which displays VPD data for
each device.

MFC 260910:
- Allow PCI devices that are attached to a driver to be identified by their
device name instead of just the selector.
- Accept an optional device argument to -l to restrict the output to only
listing details about a single device. This is mostly useful in
conjunction with other flags like -e or -c to allow a user to query
details about a single device.

MFC: r287522

Prefer pciids database from ports if present

Given the pciids database on ports is updated more often than the one in base
prefer this version if present, otherwise read the one from base.

Relnotes: yes
Differential Revision: https://reviews.freebsd.org/D3391

MFC r273488:
Fix some bugs in the error handling of getdevice().

PR: 194506

MFC r266468:
Add IOMMU PCI subclass, found on Tyan S8236 motherboard.

Submitted by: Dmitry Luhtionov <dmitryluhtionov@gmail.com>

MFC 260926:
Add support for displaying VPD for PCI devices via pciconf.
- Store the length of each read-only VPD value since not all values are
guaranteed to be ASCII values (though most are).
- Add a new pciio ioctl to fetch VPD for a single PCI device. The values
are returned as a list of variable length records, one for the device
name and each keyword.
- Add a new -V flag to pciconf's list mode which displays VPD data for
each device.

MFC 260910:
- Allow PCI devices that are attached to a driver to be identified by their
device name instead of just the selector.
- Accept an optional device argument to -l to restrict the output to only
listing details about a single device. This is mostly useful in
conjunction with other flags like -e or -c to allow a user to query
details about a single device.