[lldb] Fix pessimizing move warning

lldb/source/Core/PluginManager.cpp:695:21: warning: moving a temporary object prevents copy elision [-Wpessimizing-move]
      return Status(std::move(ret.takeError()));
                    ^
lldb/source/Core/PluginManager.cpp:695:21: note: remove std::move call here
      return Status(std::move(ret.takeError()));
                    ^~~~~~~~~~               ~