message: fix burst buffer path name on Summit
diff: @@ -70,7 +70,7 @@ This engine allows the user to fine tune the buffering operations through the fo
  13. **NodeLocal** or **Node-Local**: For distributed file system. Every writer process must make sure the .bp/ directory is created on the local file system. Required for using local disk/SSD/NVMe in a cluster.
  -14. **BurstBufferPath**: Redirect output file to another location and drain it to the original target location in an asynchronous thread. It requires to be able to launch one thread per aggregator (see SubStreams) on the system. This feature can be used on machines that have local NVMe/SSDs on each node to accelerate the output writing speed. On Summit at OLCF, use "/tmp/bb" for the path. Note: ADIOS does not remove the data on the accelerated storage after draining to the file system.
  +14. **BurstBufferPath**: Redirect output file to another location and drain it to the original target location in an asynchronous thread. It requires to be able to launch one thread per aggregator (see SubStreams) on the system. This feature can be used on machines that have local NVMe/SSDs on each node to accelerate the output writing speed. On Summit at OLCF, use "/mnt/bb/<username>" for the path where <username> is your user account name. Note: ADIOS does not remove the data on the accelerated storage after draining to the file system.
  15. **BurstBufferDrain**: To write only to the accelerated storage but do not drain it to the target file system, set this flag to false. By default, setting the BurstBufferPath will turn on draining.
  @@ -95,7 +95,7 @@ This engine allows the user to fine tune the buffering operations through the fo
  StatsBlockSize integer > 0 **a very big number**, ``1073741824`` for blocks with 1M elements
  NodeLocal string On/Off **Off**, On
  Node-Local string On/Off **Off**, On
  - BurstBufferPath string **""**, /tmp/bb, /ssd
  + BurstBufferPath string **""**, /mnt/bb/norbert, /ssd
  BurstBufferDrain string On/Off **On**, Off
  BurstBufferVerbose integer, 0-2 **0**, ``1``, ``2``
  ============================== ===================== ===========================================================
  