BUG: MPICH SEEK_SET is #defined but must not be for C++ binding

The problem is that both stdio.h and the MPI C++ interface use SEEK_SET,
SEEK_CUR and SEEK_END. This is really a bug in MPI-2 standard. Since, the Intel
MPI derives from MPICH2, using the Intel MPI interface also produces the error.
Adding the definition to ignore MPI SEEK circumvents the issue.

Change-Id: I4e7e3083baa581d8c348c547d0b88c4c87bddde6
Merge topic 'fix_intel_compiler_mpich_issues' into next

9f03a19f BUG: MPICH SEEK_SET is #defined but must not be for C++ binding