Removed duplicate file from mpi

This change removes mpi/mpiCC which was a duplicate of mpi/mpicc.
This fixes bug 1332744, "Two files with same case-insensitive name
in mpi", which made it harder to download Trafodion source to a
Windows system.

Change-Id: I343678e8275cfb820c16cc07df8297b0b8de699d
Merge "Removed duplicate file from mpi"