[PATCH] docs: document virtio-balloon stats

[Tomáš Golembiovský <tgolembi@redhat.com>]

Document statistics added in commits

    commit a0d06486b445985b8d128df172daefbae205bffd
    Author: Denis V. Lunev <den@openvz.org>
    Date:   Wed Feb 24 10:50:48 2016 +0300

        virtio-balloon: add 'available' counter

and

    commit bf1e7140ef0b3a149860ab9f05b36665133238f6
    Author: Tomáš Golembiovský <tgolembi@redhat.com>
    Date:   Tue Dec 5 13:14:46 2017 +0100

        virtio-balloon: include statistics of disk/file caches

Signed-off-by: Tomáš Golembiovský <tgolembi@redhat.com>
---
 docs/virtio-balloon-stats.txt | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/docs/virtio-balloon-stats.txt b/docs/virtio-balloon-stats.txt
index edff5f22a8..7a66d25da5 100644
--- a/docs/virtio-balloon-stats.txt
+++ b/docs/virtio-balloon-stats.txt
@@ -32,6 +32,8 @@ which will return a dictionary containing:
       - stat-minor-faults
       - stat-free-memory
       - stat-total-memory
+      - stat-available-memory
+      - stat-disk-caches
 
   o A key named last-update, which contains the last stats update
     timestamp in seconds. Since this timestamp is generated by the host,
-- 
2.16.1