winegstreamer: Use a GstAtomicQueue for wg_transform output queue.

winegstreamer: Use a GstAtomicQueue for wg_transform output queue.

Some GStreamer video plugins such as vaapi do not expect their buffers
to be appended to each other, and it breaks some of their assertions.

We will also later need to queue caps change events, and the atomic
queue will let us queue GstSample instead to hold the caps too. It also
removes the need of a mutex or locking operations.

Wine-Bug: https://bugs.winehq.org/show_bug.cgi?id=45988
Wine-Bug: https://bugs.winehq.org/show_bug.cgi?id=47084
Wine-Bug: https://bugs.winehq.org/show_bug.cgi?id=49715
Wine-Bug: https://bugs.winehq.org/show_bug.cgi?id=52183
Signed-off-by: Rémi Bernon <rbernon@codeweavers.com>
Signed-off-by: Nikolay Sivov <nsivov@codeweavers.com>
Signed-off-by: Zebediah Figura <zfigura@codeweavers.com>
Signed-off-by: Alexandre Julliard <julliard@winehq.org>