vtkmultiwriter: remove inconsistent naming for parallel output

git-svn-id: svn://svn.iws.uni-stuttgart.de/DUMUX/dumux/trunk@8145 2fb0f335-1f38-0410-981e-8018bf24f1b0

dumux/io/vtkmultiwriter.hh

@@ -362,7 +362,7 @@ private:
         if (commSize_ > 1) {
             std::ostringstream oss;
             oss << "s" << std::setw(4) << std::setfill('0') << commSize_
-                << ":p" << rank
+     	        << ":p" << std::setw(4) << std::setfill('0') << rank
                 << ":" << simName_ << "-"
                 << std::setw(5) << curWriterNum_;
             return oss.str();