I24 ssx: Address PVs that aren't part of parameters.

Some of the General Purpose PVs in use for the fixed-target are not part of the parameter model, we need to find a good way to address these:

- `GP104` to `GP108` are just displaying the result of the calculation for a good laser delay to set in the pump_probe screen, and not used again (Plan for this calculation kicked of by button).
- `GP11` to `GP74` are each assigned to one block of the oxford chip in the mapping lite screen. When 0 the block is not collected, when 1 the block is collected. These values are written to the `currentchip.map`` file when creating the map and the PVs are never used again in the script.