I/O - Determine Primary Index

[wesbland]

Problem

In constant and predefined handle index, many entries do not have a "primary" entry (where the item is first defined; other entries should be where used).

Suggested Fix

Find relevant entry; could enlist chapter committees

[wesbland]

This wasn't read at the December 2022 meeting. The last opportunity for MPI 4.1 is to have it ready at the March 2022 meeting (and it needs to "pass" the reading).

@tonyskjellum / @qkoziol / @Shinji-Sumimoto Are you (or is someone else) planning to push this forward or should we move it out of the plan for MPI 4.1?