virDomainGetTime: Deny on RO connections

We have a policy that if API may end up talking to a guest agent
it should require RW connection. We don't obey the rule in
virDomainGetTime().
Signed-off-by: NMichal Privoznik <mprivozn@redhat.com>

src/libvirt-domain.c

@@ -10934,6 +10934,7 @@ virDomainGetTime(virDomainPtr dom,
     virResetLastError();
 
     virCheckDomainReturn(dom, -1);
+    virCheckReadOnlyGoto(dom->conn->flags, error);
 
     if (dom->conn->driver->domainGetTime) {
         int ret = dom->conn->driver->domainGetTime(dom, seconds,