qmp: Switch timestamp_put() to qdict_from_jsonf_nofail()

There's just one use of qobject_from_jsonf() to parse a JSON object
left: timestamp_put().  Switch it to qdict_from_jsonf_nofail().

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-Id: <20180703085358.13941-29-armbru@redhat.com>
1 file changed