clang 10 is complaining about incompatible types due to the
glib typesystem.
```
../subprojects/gst-rtsp-server/gst/rtsp-server/rtsp-thread-pool.c:534:10: error: incompatible pointer types passing 'typeof ((((void *)0))) *' (aka 'void **') to parameter of type 'GThreadPool **' (aka 'struct _GThreadPool **') [-Werror,-Wincompatible-pointer-types]
```
Part-of: <https://gitlab.freedesktop.org/gstreamer/gst-rtsp-server/-/merge_requests/145>
if (G_UNLIKELY (!g_atomic_pointer_get (&klass->pool))) {
GThreadPool *t_pool;
t_pool = g_thread_pool_new ((GFunc) do_loop, klass, -1, FALSE, NULL);
- if (!g_atomic_pointer_compare_and_exchange (&klass->pool, (GThreadPool *) NULL, t_pool))
+ if (!g_atomic_pointer_compare_and_exchange (&klass->pool,
+ (GThreadPool *) NULL, t_pool))
g_thread_pool_free (t_pool, FALSE, TRUE);
}