Add parameter option list in full parameters list

In the full parameters list, the options for parameters such as RCx_FUNC are not listed as in Mission Planner. Having those would be very helpful, especially in the field with no internet connection to to go to the docs.

Locate the full parameters list implementation and the metadata for parameters such as RCx_FUNC, then compare the displayed options with Mission Planner. Done means the relevant parameter option lists are available in the full list for offline use and match the expected Mission Planner choices.

Written by the indexing model from the issue text.