qmp-events: move 'BALLOON_CHANGE' doc to schema

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>

docs/qmp-events.txt

@@ -1,25 +1,6 @@
                    QEMU Machine Protocol Events
                    ============================
 
-BALLOON_CHANGE
---------------
-
-Emitted when the guest changes the actual BALLOON level. This
-value is equivalent to the 'actual' field return by the
-'query-balloon' command
-
-Data:
-
-- "actual": actual level of the guest memory balloon in bytes (json-number)
-
-Example:
-
-{ "event": "BALLOON_CHANGE",
-    "data": { "actual": 944766976 },
-    "timestamp": { "seconds": 1267020223, "microseconds": 435656 } }
-
-Note: this event is rate-limited.
-
 DUMP_COMPLETED
 --------------
 

qapi/event.json

@@ -461,7 +461,16 @@
 #
 # @actual: actual level of the guest memory balloon in bytes
 #
+# Note: this event is rate-limited.
+#
 # Since: 1.2
+#
+# Example:
+#
+# <- { "event": "BALLOON_CHANGE",
+#      "data": { "actual": 944766976 },
+#      "timestamp": { "seconds": 1267020223, "microseconds": 435656 } }
+#
 ##
 { 'event': 'BALLOON_CHANGE',
   'data': { 'actual': 'int' } }