TrilinosCouplings: Fix #2281
Created by: mhoemmen
Fix #2281 (closed) (build warnings in TrilinosCouplings). It's hard to figure out how to set up TrilinosCouplings so it actually tests the thing -- I built TrilinosCouplings with ML enabled, but that didn't seem to enable the code.
@trilinos/ml @trilinos/muelu