Nit picking: Multi-function PCI Express Root Ports should mean that
'addr' property is mandatory, and slot is optional because it defaults
to 0, and 'chassis' is mandatory for 2nd & 3rd root port because it
defaults to 0 too.

Bonus: fix a typo(2->3)
Signed-off-by: Cao jin <caoj.fnst@cn.fujitsu.com>
Reviewed-by: Marcel Apfelbaum <marcel@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>