The previous style(s) used in most places here violates the C standard, and in
practice can trigger -Wreserved-id-macro in clang for client code. So, switch
to a conventional style that doesn't trigger warnings (and is supported by
tools like clang-tidy).
types.h:
Remove the definition of `jack_native_thread_t` as we will be relying on
the one from systemdeps.h.
{jack,thread}.h:
Include systemdeps.h for definition of `jack_native_thread_t`.
Nedko Arnaudov
David Robillard
David Runge
Paul Davis