Utkarsh Ayachit authored Nov 09, 2011 and Kenneth Moreland committed Nov 09, 2011

On several machines, FindMPI picks mpicxx by default. Linking with this C++
library causes issues with the C-based test executables.

FindMPI.cmake has gone revisions in recent versions of cmake (in 2.8.6 for
example). FindMPI now provides language specific MPI flags. Fixed the code to
use these MPI_<lang>_<variable> flags to avoid the afforementioned issue.