remap incorrect b2 amps when setting amp offsets

In INSTRM-1100 I only remapped the readout channels, and did not touch the command stream. But there is one top-level FEE command which controls single channels: setting the per-amp bias offsets. And the 0_1 amp has an anomalously low bias level coming into the ADC. So tuning the bias levels without accounting for the swap results in distressing results: 0-ADU 0_1 amp and a high 1_2 amp.

Confusing enough that the command should be fixed, or someone in five years will be as confused as I was today.

The really should be corrected in the ics_xcu_fpgs feeControl.py module, where both the setting and the getting can be adjusted. If that is not too messy I'll do that, else I'll just swap in the setOffsets command in the ccdActor.