The <type/> element for <capability type='scsi'> part of nodedev
XML is optional (see udevProcessSCSIDevice()) and as such might
not be formatted into nodedev XML (see
virNodeDeviceCapSCSIDefFormat()). Reflect this in our RNG.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>