audio/jack: Fix use of qemu_thread_set_name() on macOS

Since commit 8f68a33ad4 we get on macOS:

  Audio backends
    CoreAudio support               : YES
    PipeWire support                : NO
    JACK support                    : YES 1.9.22

  ../audio/jackaudio.c:654:12: error: unused function 'qjack_thread_creator' [-Werror,-Wunused-function]
    654 | static int qjack_thread_creator(jack_native_thread_t *thread,
        |            ^~~~~~~~~~~~~~~~~~~~

This is simply due to a missing #ifdef'ry change. Update
so we can use the new qemu_thread_set_name() exposed by
commit 46255cc2be.

Fixes: 8f68a33ad4 ("audio: make jackaudio use qemu_thread_set_name")
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Christian Schoenebeck <qemu_oss@crudebyte.com>
Message-Id: <20260307114923.75394-1-philmd@linaro.org>

audio/jackaudio.c

@@ -712,7 +712,7 @@ static const TypeInfo audio_types[] = {
 static void __attribute__((__constructor__)) audio_jack_init(void)
 {
     qemu_mutex_init(&qjack_shutdown_lock);
-#if !defined(WIN32) && defined(CONFIG_PTHREAD_SETNAME_NP_W_TID)
+#if !defined(WIN32)
     jack_set_thread_creator(qjack_thread_creator);
 #endif
     jack_set_error_function(qjack_error);