[Ref config] Remove a debug output line.
Change MueLu-Tpetra to MueLu in can problem T.xml file.

This will make the file work for both 32-bit and 64-bit int AlbanyT builds.
Make renaming of MueLu to MueLu-Tpetra give same preconditioner behavior.

From a comment:

//   Problem: Instead of renaming the sublist MueLu to MueLu-Tpetra,
// Piro::renamePreconditionerParamList caused a new empty sublist called
// MueLu-Tpetra to be created. Because it was empty, MueLu would behave badly,
// being given no user-set parameter values. Hence the worst-case bug was
// occurring: the program would run, but the performance would be terrible.
//   Analysis: Piro::renamePreconditionerParamList uses setName to change the
// sublist MueLu to MueLu-Tpetra. That does not actually work. But I think it's
// possible there is a bug in Teuchos::ParameterList, and setName should in fact
// work. The implementation of setName simply sets the private variable name_ to
// the new name, but it does not change the associated key in params_. I think
// that, or something related, is causing the problem. If I pin down the problem
// as a bug in Teuchos::ParameterList, then I'll submit a bug report and revert
// the following change.
//   (Temporary) Solution: Here I implement a version of
// renamePreconditionerParamList that uses set and then remove to do the
// renaming. That works, although it's probably inefficient.
//   Followup: Once I determine the exact issue with setName, I'll either (1)
// move this implementation to Piro or (2) submit a bug report and remove this
// implementation once the fix is in Teuchos::ParameterList.

The motivation for this (possibly temporary) bug fix is to make the can problem
work the same with 32-bit int and 64-bit int AlbanyT builds with the same
setting of "MueLu" in the T.xml file.