Use of a Trilinos deprecated function

warning: ‘template<class Node> class Tpetra::MpiPlatform’ is deprecated [-Wdeprecated-declarations]

Solution: see

• ROL: Purge use of Tpetra::*Platform
• Tpetra: Deprecate and remove DefaultPlatform, MpiPlatform, and SerialPlatform
• Tpetra documentation