Remove unecessary delay tracking debugging states

[talonmyburgh]

At present, we have delay tracking states:

• Delay_halfoff : Zero the fixed delay and delay rate to be applied to tuning 1, apply the fixed delay and delay rate to tuning 0 (tests applied fixed delay and delay rate).
• Delay_halfcal : Zero the delay rate applied to tuning 1, apply the fixed delay to both tuning 0 and 1, apply the delay rate to tuning 0 (tests applied delay rate).
• Delay_halfphase : Apply the fixed delay and delay rate to both tunings. Only apply fixed phase and phase rate to tuning 0, zero phase and phase rate for tuning 1 (tests applied phase and phase rate).
• Half_phasecorrection : Apply full delay and delay rate to both tunings along with full phase and phase rate. Only apply phase correction resulting from fshift and sideband to tuning 0 (tests phase correction calculation).
• Full_phasecorrection : Apply full delay and delay rate to both tunings along with full phase, phase rate and phase correction to both tunings (current operating mode).

The above varying states necessitate extra code and branching which can cause performance impacts to the repeating service operating on the F-Engine nodes. There is also a required function call that could be removed. With us requiring the delay tracking service to loop at ~10Hz, removing some of this logic could improve timing in this service.

[demorest]

Hi Talon, I don't think we have a need for any of the "half" setups (where different things are done to the two tunings) in normal operations. Those were entirely for debugging purposes. We might occasionally want to run an observation with either nothing applied at all, or possibly with fixed delays applied but no delay tracking. Are those options currently available?