BUG: collated: threaded writing accesses out-of-scope. Fixes #2257.

etc/controlDict

...AM/db/IOobjects/decomposedBlockData/decomposedBlockData.C

...AM/db/IOobjects/decomposedBlockData/decomposedBlockData.H

...IOobjects/decomposedBlockData/decomposedBlockDataHeader.C

src/OpenFOAM/db/IOstreams/Pstreams/UPstream.C

src/OpenFOAM/global/argList/argList.C

...l/fileOperations/collatedFileOperation/OFstreamCollator.C

...l/fileOperations/collatedFileOperation/OFstreamCollator.H

...eOperations/collatedFileOperation/collatedFileOperation.C

...eOperations/collatedFileOperation/collatedFileOperation.H

...erations/collatedFileOperation/threadedCollatedOFstream.C

src/Pstream/mpi/UPstream.C