dispatch_data_create(3) on macOS

The text be942fd880ed, as Mac OS X 10.8.5, Mac OS X 10.8.4, Mac OS X 10.8.3, Mac OS X 10.8.2, Mac OS X 10.8.1, Mac OS X 10.8 shipped it.

create and manipulate dispatch data objects

dispatch_data_create(3) on macOS now