QEMU commit bf1e7140e adds reporting of new balloon statistic to QEMU
2.12. Value represents the amount of memory that can be quickly
reclaimed without additional I/O. Let's add that too.
Signed-off-by: NTomáš Golembiovský <tgolembi@redhat.com>
Reviewed-by: NJohn Ferlan <jferlan@redhat.com>