They represent nanoseconds, and we accept such values already. Not that
anyone would use such values in the wild, but even one person testing
QEMU could put in a bigger value and will be bothered with validation
errors after every `virsh edit`. Also add a test for it.
Resolves: https://issues.redhat.com/browse/RHEL-1717
Signed-off-by: Martin Kletzander <mkletzan@redhat.com>
Reviewed-by: Peter Krempa <pkrempa@redhat.com>
