ICSHWI-14391: Add IO Expander PVs for PIN diode
requested to merge henriquesilva/archiver-appliance-config-aa-linac-prod:ICSHWI-14391_add_pin_diode_ioexpander into master
Closes ICSHWI-14391
This MR should be merged after !169 (merged) and !170 (merged) to avoid conflicts.