[Trig]RoiDescriptor: mark methods final
Apart from the L1-related functions, none of the methods in the RoiDescriptor class
are ever overridden. Marking them as final may allow the compiler to
perform inlining in specific scenarios. Also apply virtual/override and final to TrigRoiDescriptor.
Relates to ATR-27858 and cherry-picks the non-controversial changes from !64089 (closed).
Edited by Frank Winklmeier