kvm: Fixes #2868 libvirt resize notify failure (#2878)

Incorrect diskpath information was being sent to virsh blockresize, so the block device size was never refreshed to reflect the new disk size.
Fixes #2868

Author: kiwiflyer

scripts/storage/qcow2/resizevolume.sh

@@ -92,7 +92,8 @@ notifyqemu() {
     if `virsh domstate $vmname >/dev/null 2>&1`
     then
       sizeinkb=$(($newsize/1024))
-      virsh blockresize --domain $vmname --path $path --size $sizeinkb >/dev/null 2>&1
+      devicepath=$(virsh domblklist $vmname | grep $path | awk '{print $1}')
+      virsh blockresize --path $devicepath --size $sizeinkb $vmname >/dev/null 2>&1
       retval=$?
       if [ -z $retval ] || [ $retval -ne 0 ]
       then