Signed-off-by: NRonnie Sahlberg <ronniesahlberg@gmail.com>
[Actually, we should report it only if discard_granularity is nonzero.
 Older SBC drafts assigned 0 to thin provisioning and 1 to thick
 (resource-provisioned, they call it).  Newer drafts assign respectively
 1 and 2 - Paolo]
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>