Nima Trough: OPI values in undefined state when IOC loaded

As a user of a Nima Trough I would like the:
- Mode
- Control state
- Barrier state

Buttons to be populated with the initial value of each corresponding field. Currently on IOC startup they are in UDF alarm as they have no initial value. This is fixed by using the buttons to set a SP for each control. This means that whatever state it is initially in could be lost as the control/barrier state or mode needs to be changed each time.

This may be because they are missing a PINI on startup or need to be on a scan loop (or the underlying calc records need to be on a scan loop)

We initially saw this on INTER this cycle during a support call.

### Acceptance Criteria
- [ ] The above is fixed and tested with the real hardware

### Extra Information
This is a slightly unusual device as we talk to it via LVDCOM with the VI open.

Db can be found here: https://github.com/ISISComputingGroup/EPICS-ioc/blob/master/NIMATRO/NIMATRO-IOC-01App/Db/controls.db