Refine o2 sensor diagnostic functions: Changed implementation to ignore connection errors if analog interface is selected. Because the HUD is using cBars, the code has been modified to be compatible with the Bar units provided by the analog interface. Behavior (outofbounds) should be identical to the previous implementation.

Heinrichs Weikamp OSTC4 update files.

The builds are for testing purposes only. Be careful, they might not work and are definitely not recommended for real dives.