Pull virtio fixes from Michael Tsirkin:
"virtio and qemu bugfixes
A couple of bugfixes that just became ready"
* tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost:
virtio_balloon: fix increment of vb->num_pfns in fill_balloon()
virtio: release virtio index when fail to device_register
fw_cfg: fix driver remove