Darwin build fix: thread key destructor most likely refactored. (#169)

diff --git a/rpmalloc/rpmalloc.c b/rpmalloc/rpmalloc.c
index 72905fc..6c80c11 100644
--- a/rpmalloc/rpmalloc.c
+++ b/rpmalloc/rpmalloc.c
@@ -2486,7 +2486,7 @@
 	_memory_span_release_count_large = (_memory_span_release_count > 8 ? (_memory_span_release_count / 4) : 2);
 
 #if (defined(__APPLE__) || defined(__HAIKU__)) && ENABLE_PRELOAD
-	if (pthread_key_create(&_memory_thread_heap, _memory_heap_release_raw))
+	if (pthread_key_create(&_memory_thread_heap, _rpmalloc_heap_release_raw))
 		return -1;
 #endif
 #if defined(_WIN32) && (!defined(BUILD_DYNAMIC_LINK) || !BUILD_DYNAMIC_LINK)