mosquitto: add upstream security fix
Fixes CVE-2017-9868: In Mosquitto through 1.4.12, mosquitto.db (aka the
persistence file) is world readable, which allows local users to obtain
sensitive MQTT topic information.
Signed-off-by: Peter Korsgaard <peter@korsgaard.com>
(cherry picked from commit e51d69a3b11ae971d2aa65d6d0a6f0bb7730e0ab)
Signed-off-by: Peter Korsgaard <peter@korsgaard.com>