Consolidation with CDI-PIO (develop)

Generally, this is !11 (merged) rebased onto the develop branch.

This is the first develop-based version accepted by the Buildbot of ICON: https://buildbot.dkrz.de/grid?branch=m300488/cdi-pio-2-integration

src/pio_mpi_fw_at_reblock.c

@@ -299,7 +299,7 @@ flushReblockBuffer(aFiledataM *of, int blockBufIdx)
   MPI_Offset ofs = (MPI_Offset) blockSize
                    * (((MPI_Offset) of->pending[blockBufIdx].pass * (MPI_Offset) sizePio * of->numBlockBuf)
                       + (MPI_Offset) blockBufIdx * (MPI_Offset) sizePio + (MPI_Offset) rankPio);
-  int wsize = of->pos >= ofs + blockSize ? blockSize : (int) (of->pos - ofs);
+  int wsize = (of->pos >= ofs + blockSize) ? blockSize : (int) (of->pos - ofs);
   xmpi(MPI_File_write_at(of->fh, ofs, blockBuf, wsize, MPI_UNSIGNED_CHAR, MPI_STATUS_IGNORE));
   of->pending[blockBufIdx].pass = -1;
   of->numMsg = numMsg;