MFC 309588: Don't attach to Host-PCI bridges with a bad bus number.
If the bus number assigned to a Host-PCI bridge doesn't match the first
bus number in the associated producer range from _CRS, print a warning and
fail to attach rather than panicking due to an assertion failure.
At least one single-socket Dell machine leaves a "ghost" Host-PCI bridge
device in the ACPI namespace that seems to correspond to the I/O hub in
the second socket of a two-socket machine. However, the BIOS doesn't
configure the settings for this "ghost" bridge correctly, nor does it have
any PCI devices behind it.
git-svn-id: svn://svn.freebsd.org/base/stable/10@310487
ccf9f872-aa2e-dd11-9fc8-
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