qemuCheckpointDelete: Check VM liveness first

Move the liveness check prior to the capability check. If the VM is
offline the capabilities are not initialized and thus we'd report the
wrong error.

https://bugzilla.redhat.com/show_bug.cgi?id=1812531Signed-off-by: NPeter Krempa <pkrempa@redhat.com>
Reviewed-by: NEric Blake <eblake@redhat.com>

src/qemu/qemu_checkpoint.c

@@ -771,15 +771,15 @@ qemuCheckpointDelete(virDomainObjPtr vm,
         return -1;
 
     if (!metadata_only) {
-        if (!virQEMUCapsGet(priv->qemuCaps, QEMU_CAPS_INCREMENTAL_BACKUP)) {
+        if (!virDomainObjIsActive(vm)) {
             virReportError(VIR_ERR_OPERATION_UNSUPPORTED, "%s",
-                           _("incremental backup is not supported yet"));
+                           _("cannot delete checkpoint for inactive domain"));
             goto endjob;
         }
 
-        if (!virDomainObjIsActive(vm)) {
+        if (!virQEMUCapsGet(priv->qemuCaps, QEMU_CAPS_INCREMENTAL_BACKUP)) {
             virReportError(VIR_ERR_OPERATION_UNSUPPORTED, "%s",
-                           _("cannot delete checkpoint for inactive domain"));
+                           _("incremental backup is not supported yet"));
             goto endjob;
         }
     }