DOC: config: Explictly add supported MQTT versions

This avoids any ambiguities on supported versions. This patch depends on
129579813 ("MEDIUM: mqtt: support mqtt_is_valid and mqtt_field_value
converters for MQTTv3.1").

It must be backported with the above commit.

(cherry picked from commit 140a35766085bd900e8d9a74e3501abdb66d8a41)
Signed-off-by: Christopher Faulet <cfaulet@haproxy.com>
(cherry picked from commit 9117829adc71de07d1d7fa96bc028e870e56d60f)
Signed-off-by: Christopher Faulet <cfaulet@haproxy.com>
1 file changed