PCI: fix sysfs rom file creation for BIOS ROM shadows
At one time, if a BIOS ROM shadow was detected for the boot video
device (stored at offset 0xc0000), we'd set a special resource flag,
IORESOURCE_ROM_SHADOW, so that the sysfs ROM file code could handle
it properly. That broke along the way somewhere though, so current
kernels will be missing 'rom' files in sysfs if the video device
doesn't have an explicit ROM BAR.
This patch fixes the regression by moving the video fixup quirk to a
little later in the boot cycle (to avoid having its work undone by
PCI resource allocation) and checking in the PCI sysfs code whether
a rom file should be created due to a shadow resource, which is also
moved to a little later in the boot cycle so it will occur after the
video fixup. Tested and works on my i386 test box.