pci: add two-pass pci initialization code

pci: add two-pass pci initialization code

This patch adds a second device scan to the pci initialization, which
counts the memory bars of the various sizes and types.  Then it
calculates the sizes and the packing of the prefetchable and
non-prefetchable pci memory windows and prints the results.

The patch doesn't actually map the devices to make debugging easier.

Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>