Update the Call to MPI where const cast is needed for old implementation

Src/Files/FMpiFmaGenericLoader.hpp

@@ -113,7 +113,7 @@ public:
         std::cout << "FMpiFmaGenericWriter only works with binary file (.bfma)." << std::endl;
         std::exit(EXIT_FAILURE);
       }
-    int fileIsOpen = MPI_File_open( _parallelManager->global().getComm(), inFilename.c_str(),
+    int fileIsOpen = MPI_File_open( _parallelManager->global().getComm(), const_cast<char*>(inFilename.c_str()),
                                     MPI_MODE_WRONLY | MPI_MODE_CREATE, MPI_INFO_NULL, &_mpiFile );
     // Is it open?
     if(fileIsOpen != MPI_SUCCESS){
@@ -306,7 +306,7 @@ public:
       MPI_Type_size(MPI_INT, &sizeType) ;
       _headerSize += sizeType*2 ;
       if(myRank==0){
-          ierr = MPI_File_write_at(_mpiFile, _headerSize, &nbParticles, 1, mpiFSize_t,  MPI_STATUS_IGNORE);
+          ierr = MPI_File_write_at(_mpiFile, _headerSize, const_cast<FSize*>(&nbParticles), 1, mpiFSize_t,  MPI_STATUS_IGNORE);
         }
       MPI_Type_size(mpiFSize_t, &sizeType) ;
       _headerSize += sizeType*1 ;
@@ -341,7 +341,7 @@ public:
     std::vector<FReal> particles(maxPartLeaf*_nbDataTowritePerRecord);
     // Build the offset for eaxh processes
     FSize before=0;  // Number of particles before me (rank < myrank)
-    MPI_Scan(&nbLocalParticles,&before,1,mpiFSize_t,MPI_SUM,_parallelManager->global().getComm());
+    MPI_Scan(const_cast<FSize*>(&nbLocalParticles),&before,1,mpiFSize_t,MPI_SUM,_parallelManager->global().getComm());
     before -= nbLocalParticles ;
     MPI_Offset offset = _headerSize + sizeType*_nbDataTowritePerRecord*before;
     //