pcie, virtio: Remove redundant pm_cap
The pm_cap on the PCIExpressDevice object can be distilled down
to the new instance on the PCIDevice object.
Cc: Michael S. Tsirkin <mst@redhat.com>
Cc: Marcel Apfelbaum <marcel.apfelbaum@gmail.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Zhenzhong Duan <zhenzhong.duan@intel.com>
Reviewed-by: Eric Auger <eric.auger@redhat.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Link: https://lore.kernel.org/qemu-devel/20250225215237.3314011-5-alex.williamson@redhat.com
Signed-off-by: Cédric Le Goater <clg@redhat.com>