Sometimes it might be useful to report the capability physical
address. One example is to report the physical address of the doorbell
in order to be mapped by userspace.
Signed-off-by: Jason Wang <jasowang@redhat.com>
Link: https://lore.kernel.org/r/20210415073147.19331-7-jasowang@redhat.comSigned-off-by: Michael S. Tsirkin <mst@redhat.com>