message: utils: Link directly to core libraries when appropriate
  The `bpls` and `adios_reorganize` utilities use the core APIs directly
  and do not need to link to the public bindings libraries.  Link to the
  core libraries directly and drop use of the `adios2` legacy target.
diff: @@ -9,9 +9,15 @@ configure_file(
  @ONLY
  )
  +if(ADIOS2_HAVE_MPI)
  + set(maybe_adios2_core_mpi adios2_core_mpi)
  +else()
  + set(maybe_adios2_core_mpi)
  +endif()
  +
  # BPLS
  add_executable(bpls ./bpls/bpls.cpp)
  -target_link_libraries(bpls adios2 adios2sys pugixml)
  +target_link_libraries(bpls adios2_core adios2sys pugixml)
  target_include_directories(bpls PRIVATE ${PROJECT_BINARY_DIR})
  install(TARGETS bpls EXPORT adios2
  RUNTIME DESTINATION ${CMAKE_INSTALL_BINDIR}
  @@ -39,7 +45,7 @@ add_executable(adios_reorganize
  ./adios_reorganize/main.cpp
  ./adios_reorganize/Reorganize.cpp
  Utils.cpp)
  -target_link_libraries(adios_reorganize adios2)
  +target_link_libraries(adios_reorganize PRIVATE adios2_cxx11 ${maybe_adios2_core_mpi} adios2_core)
  install(TARGETS adios_reorganize EXPORT adios2
  RUNTIME DESTINATION ${CMAKE_INSTALL_BINDIR}
  )
  