PCI/x86: format early dump like other PCI output

Use %02x:%02x.%d rather than %02x:%02x:%02x so PCI addresses
look the same as in other parts of the kernel.

Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>