Hide PointPerfect MQTT specific functions

[nseidle]

If the user selects service other than MQTT, suppress:

• Use localized distribution
• Assist Now

[PaulZC]

Linked to this:

We use pointPerfectIsEnabled() in several places to determine if (e.g.) additional RTCM messages should be enabled - for the PPL. That's no longer true. In this case, we should (I think) be using pointPerfectMqttNeeded() instead?